The relationship between protein intake (total protein, animal-based and plant-based) and skeletal muscle injuries among dance students

Relationship between

protein intake and

skeletal muscle injuries

The relationship between protein intake (total protein,

animal-based and plant-animal-based) and skeletal muscle injuries among dance

students

A Nutrition & Dietetics Bachelor Thesis

Merel de Beus & Rynske Keur 2018116

The relationship between protein intake (total protein, animal-based and plant-based) and skeletal muscle injuries among dance students

Authors M.A. de Beus

500704507 merel.de.beus@hva.nl R. Keur 50693255 rynske.keur@hva.nl Project number 2018116

Thesis organisation Codarts Rotterdam

Supervisor Dr. J.H. Stubbe

Lector Performing Arts Medicine, Codarts Rotterdam Head Codarts Research Office, Codarts Rotterdam

M.J. Rijmenam

Employee Stagebureau Nutrition, University of Applied Sciences Amsterdam

Coordinator Amsterdam Nutritional Assessment Center, University of Applied Sciences Amsterdam

Supervising lecturer Dr. ir. M.F Engberink

Senior scientist Weight Management, University of Applied Sciences Amsterdam

Preface

As starting dieticians we feel interested in sports and nutrition. The prevention of injuries is a key factor at Codarts Rotterdam. All contributing factors are taking into consideration, including the effect of nutrition. This means that our interests in sports and nutrition are combined. The unique setting and the very talented dancers made our curiosity develop even further.

We proudly present our bachelor thesis for Codarts Rotterdam. For 20 weeks we worked with pleasure on this research. Within this thesis you will find an analysis of the relationship between type of protein intake and skeletal muscle injuries among second year contemporary dance students of Codarts Rotterdam. In the course of our research we found interesting results, which we would like to present. We hope that researchers will further delve into the nutrition factors of preventing skeletal muscle injuries.

There are a number of people we would like to thank for their feedback and collaboration. Firstly we would like to thank dr. Janine Stubbe for creating this challenging and unique opportunity. Our thanks go out to our supervising lecturer dr. ir. Marielle Engberink. Your feedback and enthusiasm has been a great help during this process. Thank you Andreas Leertouwer for giving us time during your class each week and your collaboration. Mariette van Rijmenam thank you for helping us with processing the food diaries. We are grateful that Rogier van Rijn could provide us with the data of the injuries. The accessibility and willingness of Diana van Winden, Annemiek Tiemens and Stephanie Keizer were helpful in answering our questions.

Last and certainly not least, we would like to thank the second year contemporary dance students of Codarts Rotterdam. Without your participation we would be nowhere. We enjoyed working with you and we wish you all the best in your future careers.

We jumped into this process without even knowing each other. Along the way we had so much fun together, which resulted in a final product that we are immensely proud of.

Amsterdam, 7 January 2018 Merel de Beus en Rynske Keur

Abstract

Background: Athletes are frequently at risk of getting injured. Codarts University signals many injuries among their dance students. It is important to understand the factors that could influence injuries. Nutrition and more specifically protein is one of these factors. The effects of animal-based and plant-based protein synthesis are still being studied. A combination of protein type and skeletal muscle injuries among dance students has never been examined. Therefore Codarts requested research about protein type and skeletal muscle injuries.

Method: During this cross-sectional research method, 21 second year dance students participated. Protein data were collected with a three-day food diary. The data were extracted and collected in Excel and exported to SPSS. Injury data were obtained from Codarts’ Performing Artist and Athlete Health Monitor. In SPSS mean protein intake was displayed in the categories: <1.2, 1.2-1.7 and >1.7 gram protein per kilogram body weight per day. Mean animal-based and plant-based energy in percentage per day were categorized in tertiles. These variables were added together in a table to examine the relationship between protein type and skeletal muscle injuries.

Results: Mean total protein intake was 85.4 ±28.4 gram per day. Mean animal-based protein intake was 38.6 ±26.1 gram per day and mean plant-based protein intake was 46.8 ±18.5 gram per day. The recommended protein intake of 1.2 gram per kilogram body weight per day was achieved by 66.7% (n=14). Of the students with skeletal muscle injuries (n=3) 66.7% had a protein intake >1.2 gram per kilogram body weight per day and 33.3% had a protein intake <1.2 gram per kilogram body weight per day. A more balanced ratio animal-based and plant-based protein intake occurred in students with no skeletal muscle injuries (respectively 40.1 ±27.7 and 42.2 ±14.7 gram) than in students with skeletal muscle injuries (respectively 23.3 ±12.0 and 74.6 ±15.0 gram). When animal-based protein increased and plant-based protein decreased skeletal muscle injuries decreased.

Conclusion: There is a possible relationship between protein source and the occurrence of skeletal muscle injuries. However, because of limited students with skeletal muscle injuries, this relationship is not significant.

Table of Contents

Preface

Abstract

1. Introduction

2. Method

2.1. Research design

2.2. Research population

2.3. Protein intake

2.4. Skeletal muscle injuries

2.5. Data analysis

3. Results

3.1. Research population

3.2. Protein intake

3.3. Skeletal muscle injuries

3.4. Relationship between protein and skeletal muscle injuries

4. Discussion

5. Conclusion

6. Recommendations

6.1. Protein intake

6.2. Recommendations for future research

References

Appendix

Appendix I. Three-day food diary

Appendix II. Performing Artist and Athletes Health Monitor

Appendix III. Mean protein intake per meal per student

Appendix IV. Injury diagnosis ratio

Appendix V. Skeletal muscle injury diagnosis ratio

Appendix VI. Mean energy intake per student and class schedule

Appendix VII. Recommendation for Codarts

Appendix VIII. Mean fluid intake per student

Appendix IX. Powerpoint and infographic for Codarts

1. Introduction

It is generally known that exercise has a positive effect on health. The downside of exercise is the occurrence of injuries1-3, especially within professional sports. Injuries can have a big impact on an athlete, ranging from a reduction of physical activity4,5 to ceasing their career1. There are two ways an athlete sustains an injury; acute and overuse injuries. The acute injuries occur suddenly. With these types of injuries there is a specific moment of origin. The overuse injuries develop gradually. With these types of injuries there is no specific moment of origin1,6.

Dancers are athletes and are prone to injuries4. Studies show that dancers have high injury reports throughout their careers4,8,9. Among their dance students, Codarts signals the high prevalence of injuries. Codarts is the University of the Arts situated in Rotterdam, the Netherlands. Codarts offers high-quality education in the following three disciplines: Dance, Music and Circus Arts. The majority of the students are international. After a four year education the objective at Codarts is to deliver students in the highly competitive international fine arts world7.

It is important for the dance students at Codarts to remain healthy during their education. Injuries may lead to study delay or even worse, to dropping out of the educational program. A healthy body is an important factor during a dancer’s education and career4,5_{. Therefore it is} important to get insight into the factors that can prevent a dancer’s from getting injured. As with many other sports, a dancer’s injury can be caused by a variety of factors4. Dancing is a physically demanding career. Students at Codarts have a high workload during the day4,8,10_, with a daily average of eight hours at school. The students have little time for breaks. Repetitive movement patterns is also an injury risk factor for dancers4,8_{. The high workload} and few breaks from dancing can cause fatigue. Research shows that dancers take less than sixty minutes consecutive rest during the day4_{. The long days, high workload and few breaks} that dancers have, make it also difficult for students to have an optimal nutritional intake. Nutrition is an important injury risk factor. Several studies have shown that nutrition can have an influence on injuries4,5,10_{, however a specific study on the relationship between nutrition} and injury risk in dancers is absent.

Studies show that optimal nutrition not only reduces the risk of an injury4,5_{, but it can also} optimize dance performance10_{. However, dancers are known to have a less than adequate} nutritional intake because of the leanness and low percentage body fat that is ideal in dancing4,10_{. Adequate nutritional intake starts with the total amount of energy. The body starts} using its own muscle tissue for fuel and structural functions when total energy intake is too low11,12_{. Use of muscle tissue leads to reduction of muscle mass, which has a negative} influence on muscle growth and repair12_{. In order to maintain and repair the body's muscle} mass the macronutrient protein is needed throughout the day13,14. The current recommendations for protein intake for non-athletes is 0.8 gram per kilogram body weight per day11,15,16_{. However, athletes’ muscle mass is generally larger and therefore it is believed that} athletes need to consume more protein. For that purpose the protein recommendation for athletes is 1.2-1.7 gram per kilogram body weight per day5,10,11,15-17.

Aside from the total protein recommendation of 1.2-1.7 gram per kilogram body weight per day, recent studies also focus on the influence of protein type. It appears that the protein synthesis of animal-based proteins is more effective than the protein synthesis of plant-based proteins16,18. Muscle stimulation and recovery possibly has a lower response when plant-based proteins are consumed, even with a similar intake between plant-based and animal-based proteins. Furthermore, the lower digestibility of plant-based proteins may attribute to the lower protein synthesis of plant-based protein in comparison to animal-based protein18. However, it is unknown whether the difference in protein synthesis is due to the essential

amino acid composition or something else16,18_{. Due to the unknown influence of protein type} on skeletal muscle injuries there are no recommendations for protein type intake.

There is little to no information about the relationship between nutrition on the skeletal muscle injuries of dancers. To delve into this relationship, the actual protein intake and the skeletal muscle injuries of dancers have to be examined. This results in the following research question: What is the relationship between protein intake (total protein, animal-based and plant-based) and skeletal muscle injuries in second year Dance students at Codarts Rotterdam?

2. Method

2.1. Research design

A cross-sectional research method was used to study the relationship between protein intake and skeletal muscle injuries in dance students. Dance students were asked to fill in a nutrition diary (see appendix I) for three days to collect data about their daily nutrition intake. Data on the student's injuries was extracted from the Performing Artist and Athlete Health Monitor (from now on referred to as PAHM) (see appendix II). Data analysis was conducted with the statistical program Statistical Package for the Social Science (from now on referred to as SPSS), version 24. Through the use of scientific literature, in-depth information was gathered about protein intake and skeletal muscle injuries.

2.2. Research population

The research population consisted of second year (n=21) international contemporary dance students of Codarts, University of the Arts situated in Rotterdam, the Netherlands. The dance students practice different components and techniques of dance. Ballet, modern, jazz and impro are components and techniques practiced during the education of the student7. In addition, the students also have strength and conditioning training and pilates. Codarts University specifically requested a study towards injuries among second year dance students, because injuries start occurring more frequently.

In the three-day food diary asked to specify the current diet, because this study focuses on the relationship between protein type intake and skeletal muscle injuries. The definition of various diets is shown in table 1.

Table 1 Definition of diets19

Diet Description

Pesco-vegetarian No consumption of animal flesh but fish is consumed Lacto-ovo vegetarian No consumption of all flesh but dairy and eggs are consumed Lacto vegetarian No consumption of all flesh and eggs but dairy is consumed Ovo vegetarian No consumption of all flesh and dairy but eggs are consumed Vegan No consumption of all animal products

The researchers introduced themselves to the students through the use of a presentation. During this presentation, the researcher explained what they expected from the participants. Furthermore, the food diary was presented to the students. Participants were instructed to keep a specific record of their daily nutrition and liquid intake. The participants were also asked to specify: gender, nationality, age and diet. All the private information in this study was treated with care according to guidelines provided by the Medical Ethical Committee (MEC).

2.3. Protein intake

Data of the participants protein intake was extracted by means of a three-day food diary20,21. The structure of the food diary was based on standards provided by the Amsterdam University of Applied Science (see appendix I). The food diary was translated into English, because the English curriculum of the dance education.

The participants were asked to keep track of their nutrition intake for three days, which included two weekdays and one day during the weekend. Information was gathered about the time of nutrition intake, what the participant consumed exactly and in what quantity. To

maximize response several notification emails were sent and multiple visits were made to ask the students to keep track of their consumed nutrition. All the data from the food diaries was extracted and collected in a standardized Microsoft Excel-file with the use of the Dutch Food Composition Database 201322 _{(from now on referred to as NEVO) and the nutrition table}23_. To make sure all information was correctly processed the entered data were checked twice. The Microsoft Excel-file was subsequently coded and linked to the NEVO-table. This ensured that specific nutrition information was correctly linked to consumed nutrition. Subsequently the mean nutrition intake of macro and micronutrients per person was calculated by means of a syntax in SPSS, which was provided by the Amsterdam University of Applied Sciences. The variables ‘mean protein intake in grams per day’, ‘mean animal-based protein intake in grams per day’, ‘mean plant-animal-based protein intake in grams per day’, ‘mean protein intake in grams per meal’, ‘mean animal-based protein intake in grams per meal’ and ‘mean plant-based protein intake in grams per meal’ were used from the SPSS-file. To show the data dispersion, standard deviation was also included. Furthermore the recommended and actual protein intake was measured in grams per kilogram body weight per day for each student. Scientific literature was used as a benchmark for recommendations about daily protein intake in grams per kilogram15-17,24 (see table 2).

Table 2 Recommended protein intake for non-athletes and athletes (male and female)15-17,24

Literature Recommendation for non-athletes Recommendation for athletes

Naderi et al. (2016) 0.8 g/kg/day* 1.2 - 2.0 g/kg/day

Joy et al. (2013) 0.8 g/kg/day 1.2 - 2.0 g/kg/day

Jager et al. (2017) 0.8 g/kg/day 1.4 - 2.0 g/kg/day

Rodriquez et al. (2009) 0.8 g/kg/day 1.2 - 1.7 g/kg/day * g/kg = grams per kilogram body weight per day

2.4. Skeletal muscle injuries

Data on the injuries, including skeletal muscle injuries, were obtained by means of the PAHM from Codarts (see appendix II). The PAHM is standardized and created according to the official protocol of Codarts. This questionnaire was assessed on a monthly basis. This way Codarts was kept up to date on the health status (physical health, mental health, sleep disorders, feelings and their emotions for the past four weeks) of the students. All data were stored automatically in a general database. Cleaning of the data were performed by researchers from Codarts.

The team of Codarts provided all of the data about injuries collected from the PAHM from the months September, October and November of the year 2017. Encrypted as SPSS-file, this data were sent to the researchers. The data on injuries was categorized into ‘skeletal muscle injury’ and ‘no skeletal muscle injury’. Subsequently, Fuller et al. (2006) proposed that injuries could be allocated into two different subcategories. When someone receives medical attention, the injury is referred to as a medical attention injury25_{. Furthermore, if someone is} unable to participate in training or a performance, the injury is referred to as a time-loss injury. An injury can thus be classified as both medical-attention and time-loss injury.

The PAHM categorizes different injuries and symptoms. The injury diagnoses on the monitor are the following: bone fracture, other bone injury, joint dislocation / subluxation, joint inflammation, sprain / ligament injury, ligament rupture, lesion of meniscus or cartilage, muscle strain / tear, muscle rupture, muscle cramps, inflammation of a bursa, tendinosis, tendon strain / tear, tendon rupture, hematoma / contusion / bruise, laceration / abrasion, concussion, nerve injury, dental injury, unknown and other. There is a difference between skeletal muscle injuries and no skeletal muscle injuries injuries1. According to literature the

following diagnoses include skeletal muscle injuries: muscle strains / tear, muscle cramp, muscle contusion, muscle avulsion / detachment, torn ligament, tendon twitching and tendon rupture26,27_.

Included in this study are the PAHM injury diagnosis, medical-attention and time-loss injury. For a total of all injuries in the investigated three months, the injuries were classified in subcategories. The categories ‘total injuries per month’, ‘students with injury per month’ and ‘skeletal muscle injuries per month’ were created in the SPSS-file. Students who did not answer the questions about injury diagnosis were nominal encoded with no injury. Furthermore, the variables ‘number of time-loss injuries per month’ and ‘number of medical attention injuries per month’ were created, and an average days missed was calculated for time-loss injuries.

2.5. Data analysis

Second year dance students who did not participate in this study were filtered out of the PAHM database (n=6).

By using Descriptive Statistics, the average protein intake in grams per day and in grams per eating moment, and the average animal-based and plant-based protein intake in grams per day, were calculated. Protein recommendation per kilogram body weight per day for each student was calculated using Compute Variable. The body weight of each student was divided by de recommended protein intake of 1.2 and 1.7 respectively in order to display the recommended amount of protein in grams per day. The students were categorized by gram protein per kilogram body weight per day according to the literature. The categories were defined as <1.2 gram per kilogram body weight, 1.2-1.7 gram per kilogram body weight and >1.7 gram per kilogram body weight protein intake per day. The percentage of these categories was calculated using Descriptive Statistics. Within the three categories an average protein intake in gram per kilogram body weight and average protein intake in grams per day was calculated. These results were put into a table and the categories are shown in a graphic. The questions concerning the diagnosis of injuries, from the months September, October and November were encoded at nominal level (yes/no) in SPSS. Missing value was encoded with ‘no’. Using Descriptive Statistics, the number of students with injury and total injuries per month was established. Furthermore the percentage of students with injury per month was calculated. The skeletal muscle injuries per month were established with Descriptive Statistics. The percentage of skeletal muscle injuries was calculated. Shown in a table are the number of injured students, number of total injuries and number of skeletal muscle injuries. Furthermore the stacked bar was used to show the cumulative value of all injuries and skeletal muscle injuries both per month and in total. Students who did not recover from injury were counted once in the total number of injuries. In addition, every injury was checked for time-loss and if the students had medical-attention. The average days missed were calculated with Descriptive Statistics.

The data of the three-day food diary and the skeletal muscle injuries were combined and analysed in SPSS. Using Compute Variable the kilocalories per day of both animal-based and plant-based proteins were calculated. From there the energy percentage of kilocalories per day of animal-based and plant-based proteins were calculated using compute variable.

The relationship between protein type intake and skeletal muscle injuries was examined by means of energy percentage of both animal-based and plant-based protein. The energy percentage of animal-based protein was sorted in ascending order. Subsequently the population was classified in tertiles. Of each category the mean total, animal-based and plant-based protein intake was calculated using Descriptives. Furthermore the mean animal-plant-based energy percentage was calculated for each tertile. To see the relationship between

animal-based protein intake and skeletal muscle injuries, the skeletal muscle injuries were displayed per tertiles. The same steps were taking for plant-based protein.

3. Results

3.1. Research population

Of the 27 second year contemporary dance students, 21 students (77,8%) were willing to participate in the study. All the included students (n=21) filled in the PAHM. In the included group 38% (n=8) were male and 62% (n=13) were female. The students came from Italy (n=5), France (n=3), Portugal (n=2), Spain (n=2), Albania (n=1), Croatia (n=1), Denmark (n=1), Germany (n=1), Japan (n=1), Luxembourg (n=1), Netherlands (n=1), Slovenia (n=1) and Turkey (n=1). Students followed either no diet (n=17), a pesco-vegetarian diet (n=2), a lacto-ovo vegetarian diet (n=1) or a vegan diet (n=1). The mean age of the population is 19.4 ±0.7 years. The mean BMI of the population is 20.9 ±1.4 kilogram per square meter.

3.2. Protein intake

The data analysis showed that the mean protein intake is 85.4 ±28.4 grams per day and 1.5 ±0.4 gram per kilogram body weight per day. In addition the results show that the mean plant-based protein intake is 8.2 grams higher than the mean animal-plant-based protein intake. Furthermore the protein intake fluctuates during the day, from 2.9 grams at the first break to 34.0 grams at diner (see table 3 and appendix III)

Table 3: Overview of mean protein intake in students (n=21) Mean protein Protein in g/day* 85.4 ±28.4 Protein in g/kg 1.5 ±0.4 Animal-based in g/day 38.6 ±26.1 Plant-based in g/day 46.8 ±18.5 Breakfast in g/day 18.2 ±8.3 Break 1 in g/day 2.9 ±2.4 Lunch in g/day 23.0 ±10.9 Break 2 in g/day 9.2 ±6.5 Dinner in g/day 34.0 ±19.5 Break 3 in g/day 3.3 ±4.6 * g/day = gram per day

A total of 66.7% (n=14) students had a protein intake of more than 1.2 gram protein per kilogram body weight per day. A percentage of 23.8 (n=5) from the total students had a protein intake of >1.7 gram per kilogram body weight per day. Furthermore the results show that 7 students are below the recommendation of 1.2 gram protein per kilogram body weight per day (see table 4 and figure 1).

Table 4: Overview of protein intake in categories with corresponding mean g/kg and mean g/day intake

<1.2 g/kg 1.2-1.7 g/kg >1.7 g/kg Students n=7 (33.3%) n=9 (42.9%) n=5 (23.8%)

Mean g/kg 1.0 ±0.2 1.5 ±0.1 2.0 ±0.2

Figure 1: Mean protein total in grams per day with recommendation per student (n=21)

Figure 2 shows the mean protein intake per day per students, divided in animal-based and based protein in grams per day. Of the students 61.9% (n=13) had a higher mean plant-based protein intake than animal-plant-based protein intake. A percentage of 38.1 (n=8) had a higher mean animal-based protein intake than plant-based protein intake.

3.3. Skeletal muscle injuries

The data analysis shows that 25 injuries were recorded over three months among 21 students. Of the total number of injuries (n=25) 20% (n=5) is a skeletal muscle injury (see table 5). Appendix IV shows the diagnosis of the all injuries.

Table 5: Number of students with injury, total number and percentage of students with injury, and students with skeletal muscle injury, number and percentage of skeletal muscle injuries per month and in total

All Injuries Skeletal Muscle Injuries

Number of students with injury Number of injuries Percentage of students with injury Number of students with skeletal muscle injury Number of skeletal muscle injuries Percentage of skeletal muscle injuries September 9 12 43% 3 3 25% October 6 6 29% 1 1 17% November 6 7 29% 1 1 14% Total 25 5 20%

Of the total number of injuries (n=25) over three month, 48% (n=12) occurred in September, 24% (n=6) occurred in October and 28% (n=7) occurred in November. From the total skeletal muscle injuries (n=5), 60% (n=3) occurred in September, 20% (n=1) occurred in October and 20% (n=1) occurred in November (see figure 3). Appendix V shows the diagnosis of the skeletal muscle injuries in percentage.

Figure 3: Number of total injuries per month and total injuries over three months

Table 6 shows that of the 5 skeletal muscle injuries 4 could be defined as medical attention injuries and 2 can be defined as time-loss injury. The average days missed of skeletal muscle injury is 8 days missed over three months. Of the 20 no skeletal muscle injuries 11 can be defined as medical attention injury and 14 can be defined as time-loss injury. The average days missed of no skeletal muscle injury is 11 days missed over three months.

Table 6: Skeletal muscle injuries and no skeletal muscle injuries overview of medical attention and time-loss injuries Medical attention injuries Time-loss injuries

Average days missed of time-loss injuries Skeletal muscle injuries (n=5) 4 2 8.0 ± 9.9 No skeletal muscle injuries (n=20) 11 14 10.9 ±12.1

3.4. Relationship between protein and skeletal muscle injuries

Of the 21 students 3 students (14.3%) sustained a skeletal muscle injury. Table 7 shows that 66.7% (n=2) of the students with a skeletal muscle injury meet the recommendation of 1.2-1.7 gram protein intake per kilogram body weight per day. Furthermore, it is shown that 33.3% (n=1) of the students with a skeletal muscle injury is below the recommendation of 1.2 gram protein intake per kilogram body weight per day. Among the 21 students 85.7% (n=18) did not sustain a skeletal muscle injury. Of these 18 students 33.3% (n=6) had a protein intake below the recommended 1.2 gram per kilogram body weight per day (see table 7).

Table 7: Relationship between amount of protein intake and skeletal muscle injuries (n=5) and no skeletal muscle injuries (n=20) among dance students (n=21)

<0.8 g/kg Protein Intake 0.8-1.2 g/kg Protein intake 1.2-1.7 g/kg Protein intake >1.7 g/kg Protein intake Total Skeletal muscle injury 1 2 3 No skeletal muscle injury 1 5 7 5 18 Total 1 6 9 5 21

When focussing on protein type the following relationship was found. An increased animal-based protein intake shows a decreased number of skeletal muscle injuries. In addition, table 8 shows that plant-based protein intake decreases when the mean animal-based energy percentage increases.

Table 8: Relationship between animal-based energy in percentage in tertiles and skeletal muscle injuries among dance students (n=21)

T1 (n=7) T2 (n=7) T3 (n=7) Mean animal-based energy in

percentage

2.9 ±1.3 5.4 ±0.4 11.1 ±3.9

Total gram per day 77.8 ±18.5 79.4 ±28.0 98.8 ±35.2

Animal-based in gram per day 19.5 ±9.1 33.9 ±14.6 62.3 ±29.4

Plant-based in gram per day 58.4 ±17.1 45.5 ±20.6 36.5 ±11.9

As the plant-based protein intake increases, the number of skeletal muscle injuries also increases. In addition, the table shows that animal-based protein decreases when the mean plant-based energy percentage increases. Furthermore the total gram per day is lower in tertile 2 (78.5 ±22.7 gram per day) in comparison than tertile 1 (87.3 ±35.3 gram per day) (see table 9).

Table 9: Relationship between plant-based energy in percentage in tertiles and skeletal muscle injuries among dance students (n=21)

T1 (n=7) T2 (n=7) T3 (n=7) Mean plant-based energy in

percentage

5.4 ±1.2 7.8 ±0.9 10.4 ±2.2

Total gram per day 87.3 ±35.3 78.5 ±22.7 90.2 ±28.9

Animal-based in gram per day 54.4 ±33.5 32.9 ±17.7 28.5 ±19.6

Plant-based in gram per day 33.0 ±5.3 46.6 ±15.9 61.7 ±19.4

Skeletal muscle injuries n=0 n=2 n=3

Table 10 shows the mean total, animal-based and plant-based protein intake of students with skeletal muscle injuries and students with no skeletal muscle injuries. Students with skeletal muscle injuries (n=3) had a higher total protein intake (103.8 ±26.9 gram per day) than students with no skeletal muscle injuries (n=18) (82.3 ±28.1 gram per day). The students with skeletal muscle injuries also had a higher consumption of plant-based protein (74.6 ±15.0 gram per day) compared to students without a skeletal muscle injury (42.2 ±14.7 gram per day). In addition the average of animal-based protein intake of students with skeletal muscle injuries (29.3 ±12.0 gram per day) was lower compared to students without a skeletal muscle injury (40.1 ±27.7 gram per day) (see table 10).

Table 10: Mean total, animal-based and plant-based protein of students with skeletal muscle injuries (n=3) and students with no skeletal muscle injuries (n=18)

Mean total protein intake in gram per day

Mean animal-based protein intake in gram per day

Mean plant-based protein intake in gram per day Students with skeletal

muscle injury (n=3)

103.8 ±26.9 29.3 ±12.0 74.6 ±15.0

Students with no skeletal muscle injury (n=18)

4. Discussion

The relationship between protein intake (total, animal-based and plant-based protein) and skeletal muscle injuries was investigated among second year dance students (n=21) from Codarts university Rotterdam. The students had a mean total protein intake of 85.4 ±28.4 gram per day and 25 injuries, including 5 skeletal muscle injuries, occurred in three months. The results show that 33.3% (n=7) of the population had a protein intake below the recommended 1.2 gram per kilogram body weight per day and 1 (33.3%) student with skeletal muscle injury occurred in this category. A percentage of 42.9% (n=9) of the population had a protein intake of 1.2-1.7 gram per kilogram body weight per day. Within this category 66.7% (n=2) of the students with skeletal muscle injuries (n=3) met these recommendations. The remaining 23.8% of the total population (n=5) had a protein intake higher than 1.7 gram per kilogram body weight per day. When focussing on the relationship between protein type and skeletal muscle injuries the results show that students with skeletal muscle injuries had a lower animal-based protein intake (29.3 ±12.0 gram per day) than the animal-based protein intake (40.1 ±27.7 gram per day) of students without skeletal muscle injuries. In addition the students without skeletal muscle injuries have a more balanced animal-based (40.1 ±27.7 gram per day) and plant-based (42.2 ±14.7 gram per day) protein intake than students with skeletal muscle injuries respectively 23.3 ±12.0 and 74.6 ±15.0 gram per day. The results have shown that when animal-based protein consumption increases and plant-based protein consumption decreases, the chance of skeletal muscle injuries occurring decreases. Furthermore, when plant-based protein consumption increases and animal-based protein consumption decreases, the chance of skeletal muscle injuries occurring increases.

The recommended protein intake for non athletes is 0.8 gram per kilogram body weight per day11,15,16_{. Athletes are recommended to consume a higher protein intake than non athletes} because proteins are needed for preservation, recovery and building of the muscles11,28,29. The results show that the dance students had an average protein intake of 85.4 ±28.4 gram per day, which is similar to the average protein intake of Dutch young adults non athletes is 83.5 grams per day30_{. When looking at the recommendations of protein in gram per kilogram body} weight per day 66.7% (n=14) meet the recommended 1.2 gram protein per kilogram body weight per day, whereas, the remaining 33.3% (n=7) had a protein intake below the recommended 1.2 gram protein per kilogram body weight per day. In order to use protein effectively sufficient energy intake is required11_{. Because dancers ideally have a low} percentage of body fat, sufficient energy intake is not always naturally covered4,10_{, as is} evident in appendix VI. Because of the low energy intake it is possible that, even though 66.7% of the population meets the protein recommendation of 1.2 gram protein per kilogram body weight per day, the consumed protein is not used effectively for preservation, recovery and building of the muscles11,29_{. Therefore, it is important that the students consume sufficient} energy. Energy recommendation has to be calculated for each student based on their weight, length, age and daily activity level. In addition it is important that the students at least have a protein consumption that meets the recommendation of 1.2 gram per kilogram body weight per day.

Students with a higher consumption of animal-based protein (40.1 ±27.7 gram per day) had less skeletal muscle injuries whereas students with a lower consumption of animal-based protein (29.3 ±12.0 gram per day) had more skeletal muscle injuries. Furthermore, students with a lower consumption of plant-based protein (42.2 ±14.7 gram per day) had less skeletal muscle injuries whereas students with a higher plant-based protein consumption (74.6 ±15.0 gram per day) had more skeletal muscle injuries. A factor that possible influences these results is diet. Of the students with skeletal muscle injuries (n=3) 33.3% followed no diet, 33.3% followed a pesco-vegetarian diet and 33.3% followed a lacto-ovo vegetarian diet. In vegetarian diets there is little to no consumption of animal flesh and more consumption of vegetables and meat substitutes19. The animal-based protein consumption is therefore lower and the plant-based protein consumption is higher in these diets. However there are also

students with a pesco-vegetarian diet (n=1) and a vegan diet (n=1) that had no skeletal muscle injuries. Possibly this is because these students had a higher total protein consumption than the students with skeletal muscle injuries and vegetarian diets. According to literature vegans and vegetarians need to consume a higher amount of total protein than non vegans and vegetarians31,32_{. Because the different structures in amino acids, animal-based proteins are} more easily incorporated in the blood than plant-based proteins11,18,23_{. Therefore the} digestibility of plant-based proteins is lower than the digestibility of animal-based proteins. For the same result in preservation, recovery and building of the muscles a higher consumption of total protein is possible needed for vegans and vegetarians than for no vegans and vegetarians31.32_{. Besides nutrition there are other factors that have to be taking into} account. Students have a high workload during the day, there is little time for breaks and the repetitive movement patterns are risk factors for the occurrence of injury among dancers4,8_. Research states that animal-based protein is more effectively digested in the human body than plant-based protein16,18_{. The results show that with a higher intake of animal-based protein} less skeletal muscle injuries occurred. However, the results of this study can be misleading. Of the students with skeletal muscle injuries (n=3) 66.7% had a protein intake in the recommended area of 1.2-1.7 gram protein per kilogram body weight per day. Furthermore it also shows that of the students with no skeletal muscle injuries (n=18) 5.6% had a protein intake below 0.8 gram per kilogram body weight per day and 27.8% had a protein intake of 0.8-1.2 gram per kilogram body weight per day. In addition the results also show that the total protein intake is higher in students with skeletal muscle injuries (103.8 ±26.9 gram per day) than in students with no skeletal muscle injuries (82.3 ±28.1 gram per day). Possible this is due to the ratio male and female in both groups. The students with skeletal muscle injuries are possible mainly male. This could result in a higher protein intake, whereas in the group with no skeletal muscle injuries are more female students. Which could bring the total protein intake down. An important factor that influences these results is the small research population (n=21) and the limited injured students (n=3). Furthermore it is possible that more skeletal muscle injuries occurred than included in this research. This may be due to the diagnosis ‘unknown’ and ‘other’ from PAHM, which respectively account for 56% and 8% of total injuries. These injuries could have been skeletal muscle injuries or could end up being skeletal muscle injuries. Therefore these results have to be interpreted very carefully.

Of the 27 second years contemporary dance students 21 students were willing to participate in the research. The remaining 6 students either had no time, did not want to participate, did not see the point in participating, lost the food diary or forgot to fill in the food diary. The included group consisted of 38% male and 62% female and everyone filled in the 3 months PAHM. The results of this study should be interpreted with some caution, since there is subjectivity involved in filling in the three-day food diary. Given responses are likely to be either exaggerated or understated. Examples for reasons of subjectivity in the responses can be to create a more positive image about the students or meeting certain standards set by the outside world. Furthermore, due to the small research population and limited injured students it was not possible to test the results for statistical significance.

Because this is the first research in this field, it is advisable for follow-up studies to study protein intake and skeletal muscle injuries in other semesters of the academic year. By doing so data on injuries and protein intake increases. In addition a larger research population is advisable. This makes it possible to examine the relationship between protein type intake and skeletal muscle injuries on a more representative level. Research indicates that the number of skeletal muscle injuries can be different later in the academic year. Since this study is only about the months of September, October and November, it could be meaningful to do a research later in the semester. For better assessing the influence of protein intake on skeletal muscle injuries, correcting for the confounder energy is important. It is also necessary that the unknown diagnoses should be classified in skeletal muscle injuries or no skeletal muscle injuries. This way there are possibly more diagnosis to examine. Future research is

recommended to assure the validity of this study. Dancers are not the only group of athletes who are affected by skeletal muscle injuries. Therefore it is important that this study not only be performed on this particular group, but also varying groups of athletes. This will, in turn, deliver better and more accurate results than before. With more research the social relevance can be extended, thereby increasing the generalizability of this research. The role of animal-based and plant-animal-based protein on skeletal muscle injuries also needs to be further examined and discussed. By doing so, more can be said about the relationship between protein type and skeletal muscle injuries. With enough credible evidence a guideline of protein type ratio is a possibility.

5. Conclusion

In the present cross-sectional study among 21 second year dance students of Codarts Rotterdam the relationship between protein intake (total protein, animal-based and plant-based) and skeletal muscle injuries was studied.

The results of this cross-sectional study with 21 dance students show that 5 skeletal muscle injuries occurred. The mean protein intake was 85.4 ±28.4 gram per day and 1.5 ±0.4 gram per kilogram body weight per day. No skeletal muscle injuries were found among students who had a protein intake of >1.7 gram protein per kilogram body weight per day. There is a possible trend in the relationship between protein source and the occurrence of skeletal muscle injuries. It seems that a higher plant-based and lower animal-based protein intake results in more skeletal muscle injuries. However, it was not possible to test the statistical significant relationship between protein type intake and skeletal muscle injuries due to the small research population, few skeletal muscle injuries and short research period. Therefore the recommended 1.2-1.7 gram protein per kilogram body weight per day will be maintained.

6. Recommendations

6.1. Protein intake

The results show that multiple students do not meet the recommendation of 1.2-1.7 gram protein per kilogram body weight per day. Research states that adequate protein intake is important for the recovery of muscles. It is therefore recommended that the dance students at least have a protein intake of 1.2 gram per kilogram body weight per day. To meet the recommendation protein intake can be spread out during the day. According to literature an intake of 20 to 25 grams of protein per meal (breakfast, lunch and diner) is recommended 13,34-36_{. Besides the functional importance it is also much easier to achieve the total amount of} protein intake when divided into portions during the day. The next table shows some practical tips in order to achieve the recommendation of protein intake:

Table 11: Products containing protein

Products* High protein Medium protein Low protein

Snacks • Protein bar (25 gram)

• Breaker High Protein (16 gram)

• Nuts (see Nuts) • Energy bar (5 gram) • Snickers (5 gram) • Chocomel (6 gram) • Fruit (1 gram) Spreads • Cheese • Meat • Peanut butter • Hummus (4 gram)

• Pate (2 gram) • Jam • Sprinkles • Chocolate paste (0 gram)

Dairy

(per 100 gram)

• Skimmed and semi-skimmed quark(12 gram)

• Skimmed Greek yoghurt • Full fat quark

(8 gram) • Milk • Buttermilk • Yoghurt • Vla • Pudding (3-4 gram) Nuts and seeds

(Per hand = 25 gram Per serving spoon = 15 gram) • Peanut • Almonds • Pistache • Cashew nuts • Pumpkin seeds (5 gram) • Walnut • Hazelnut • Brasil nut (3-4 gram) • Macadamia • Pecans (2 gram) • Linseed

• Chia seed (3 gram)

Legumes / vegetables (Per 100 gram) • Soybeans (20 gram) • Black beans • White beans • Lentils • Chickpeas (7-9 gram) • Spinach • ½ avocado • Broccoli • Brussel sprouts • Kale • Green beans • Peas, • Taugé • Mushrooms (2-4 gram) Grains / cereals

(Per serving spoon = 15 gram) • Quinoa • Oatmeal (2-3 gram) • Muesli • Brinta

• Whole wheat pasta, • Couscous

(1.5 gram)

• Rice • Cornflakes (1 gram)

Meat substitutes / Meat / fish

• All meat substitutes, meat and fish (15-25 gram)

• Egg (6 gram)

* Products are in portion size.

Appendix VIII shows the recommendations of energy and fluids.

6.2. Recommendations for future research

For the relevant staff members of Codarts Rotterdam it is recommended to introduce the three-day food diary at the start of the first year of the dance education. By doing so more information on nutrition intake can be gathered over a longer period of time. It is advisable to collect information on nutrition twice a year (September and February) throughout the entire curriculum. This ensures an optimal way of linking nutrition to injuries. The questionnaire about injuries is taken once a month. However, since the nutrition pattern doesn't really change that frequently it is deemed enough to gather data twice a year about nutritional facts. Future research could also focus on the development of dance students for multiple years. Students’ nutrition possibly changes during the first year, since most students are living on their own for the first time. Therefore it could be interesting to follow the students during their education. Hereby students can be followed over a period of time and it is possible to see the choices they make on nutrition habits.

By increasing the dataset it could also be possible to study groups with different types of diets and how the diets affect the skeletal muscle injuries. Examples for different kinds of diets are: vegetarian, vegan and no specific diet.

Lastly, another recommendation for Codarts Rotterdam is a mandatory annual consult with a dietician. Especially during the first two years of the students’ education it could greatly improve the nutritional knowledge of the students. By providing students with this source of extra information, a good foundation about nutrition could be created and it could increase the awareness about the relationship between nutrition and skeletal muscle injuries.

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http://kiss.kstudy.com/search/detail_page.asp?key=3496121

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Appendix

Appendix I

Three-day food diary

Initials:_______________________________________________________________

_____________________

Age:_________________________________________________________________

_______________________

Nationality:___________________________________________________________

____________________

Male or female

Do you follow a specific diet, if yes, which diet?

_____________________________________________________________________

________________________

If you have any questions or concerns, please contact us at: Merel.de.Beus@hva.nl or the following number: +31621651825

Hi there,

We would like to thank you for participating in our research. In front of you will find our 3 day food diary. It is necessary that you fill in this diary as specific as possible. This will give us the best result and we will translate these results into tips and tricks for you! Here is a little tip already: keep this food diary at hand. When you immediately write down what you are eating, you won’t forget to write it down later that day.

So, we ask you to:

● Fill in this diary for 3 days, preferably 2 weekdays and 1 day during the weekend. ● Be as accurately as possible about your nutrition intake during the day. Nutrition

intake also includes drinks.

● Indicate how much you eat and drink and what type of food it was. ● Don’t forget snacks and fruits.

When you completed filling in your diary you can hand it in at STIP. There will be a box that says food diaries. The latest possibility for dropping it off at STIP is 12th october.

Thanks and good luck! With kind regards,

Merel de Beus & Rynske Keur Nutrition & Dietetics Thesis students

Important notes and a few examples

As we mentioned before, you have to be as specific as possible. With nutrition there are a few things that are important. Below you will find a list of how we would like you to write down your choices:

● 1 apple

● 3 small/medium/big potatoes

● 1 bowl of skimmed/semi-skimmed/full fat yoghurt ● 1 glass of water

● 1 serving spoon broccoli

● Milk: Full fat, semi-skimmed, skimmed, soy, almond ● Bread: White, brown, whole wheat, multigrain, corn ● Margarine: diet, light, Pro-activ

Then we have a few examples of how to fill in your diary. Breakfast

Time Quantity Product Type or brand

7:30 2 slices Bread Whole wheat

For 2 slices of bread Margarine Becel original

1 slice Cheese 48+

2 slices Roast beef

1 glass Milk Semi skimmed

1 glass Tea

1 Orange

During the afternoon

Time Quantity Product Type or brand

14:00 3 hands Potato chips Light

1 bottle Gatorade

16:00 1 cup Chicken soup cup-a-soup

16:30 1 glass Apple juice

2 Peaches

Dinner

Time Quantity Product Type or brand

18:00 3 servings spoons Tagliatelle pasta White

1 tablespoon Olive oil

75 gram Minced beef Beef

2 Tomatos

1/2 Union

2 serving spoon Spinach A la creme

3 tablespoons Parmesan cheese

2 glasses Water

Everybody has a different size of glass, coffee/tea cups or bowls. So we would like you to measure these sizes.

Coffee cup:________________________ml Teacup:____________________________ml Glass:______________________________ml Yoghurt bowl:_____________________ml

For the last time:

It is important that you are as accurate and honest as possible when you are writing down your diet. So we can get the best possible picture of your diet.

Day 1

Day of the week:

___________________________________________________________________________

Breakfast

Time Quantity Product Type or brand

During the morning

Lunch

Time Quantity Product Type or brand

During the afternoon

Dinner

Time Quantity Product Type or brand

During the evening

Time Quantity Product Type or brand

Comments:

__________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________

Day 2

Day of the week:

___________________________________________________________________________

Breakfast

Time Quantity Product Type or brand

During the morning

Lunch

Time Quantity Product Type or brand

During the afternoon

Dinner

Time Quantity Product Type or brand

During the evening

Time Quantity Product Type or brand

Comments:

__________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________

Day 3

Day of the week:

___________________________________________________________________________

Breakfast

Time Quantity Product Type or brand

During the morning

Lunch

Time Quantity Product Type or brand

During the afternoon

Dinner

Time Quantity Product Type or brand

During the evening

Time Quantity Product Type or brand

Comments:

__________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ Thank you for filling in our food diary.

Appendix II

PERFORMING ARTIST AND ATHLETES HEALTH MONITOR 2017-2018

First + last name: ………

1. Please indicate on the line below how much pain you had in the past four weeks, in general.

0 100

No pain Worst pain you can imagine

2. Please indicate on the line below how much stress you experienced in the past four week, in general.

0 100

No stress at all Extreme amounts of stress

The following questions are about the severity of health problems you might have had in the past four weeks. If you had several health problems, please refer to the most severe problem. Other problems can be indicated at the end of the questionnaire. Health problems refer to injuries, mental complaints or other health problems (including illnesses,

accidents, surgery et cetera).

3. Have you had any difficulties participating in class activities or performances due to health problems (injuries, mental complaints or other health problems) the past four weeks?

□0 Full participation without health problems

□8 Full participation, but with injury, mental complaint or other health problem □17 Reduced participation due to injury, mental complaint or other health problem □25 Cannot participate due to injury, mental complaint or other health problem

4. To what extent have you reduced the volume of your class activities or performances due to health problems the past four weeks?

□0 No reduction □6 To a minor extent □13 To a moderate extent □19 To a major extent □25 Cannot participate at all

5. To what extent has your health problem affected your performance the past four weeks? □0 No effect

□6 To a minor extent □13 To a moderate extent □19 To a major extent □25 Cannot participate at all

6. To what extent have you experienced health complaints the past four weeks? □0 No health complaints

□8 To a mild extent □17 To a moderate extent □25 To a severe extent

-> Go to question 37 when all answers on questions 3 until 6 are 0.

7. Is the health problem referred to in the previous questions an injury, mental complaint or something else?

□ 1 Injury -> Go to question 10

□ 3 Mental complaint -> Go to question 18

□ 4 Other complaint (for example the flu, fever, an allergic reaction, accidents, operations et cetera): ……… 8. Have you mentioned this complaint in the previous questionnaire?

□0 No □1 Yes

9. Please state the number of full days in the past four weeks that you completely/partly missed your dance/circus classes or activities due to your health problem.

… days -> Go to question 21

10. Have you mentioned this injury in the previous questionnaire? □0 No

□1 Yes

11. Is the injury/complaint a recurrent one? □0 No, new

□1 Yes, I was previously injured in this body part

□2 It is still the same injury/complaint (not recovered in between) -> Go to question 14

12. Did your injury occur during dance/circus activities? □1 Yes

□ otherNo, injury occurred during: ……… 13. Is the injury caused by overuse or trauma? When we speak of ‘trauma’ this indicates an

injury that occurred suddenly. So there is a clear moment in time at which the injury occurred. This could also indicate an accident. We speak of 'overuse injuries', in case the injury occurred over a longer period of time.

□1 Trauma □2 Overuse

14. Which part of your body is injured? If several body parts were injured, please refer to the body part that was most severely injured. Other injuries can be filled in further down the questionnaire.

□1 Head/face □2 Neck □3 Shoulder □4 Clavicle □5 Upper arm □6 Elbow □7 Forearm □8 Wrist □9 Hand/fingers/thumb □10 Chest (incl. organs) □11 Lower back (incl. coccyx) □12 Buttocks

□13 Abdomen (incl. organs) □14 Hip

□15 Groin

□16 Upper leg (front) □17 Upper leg (back) □18 Knee

□19 Upper back

□20 Lower leg (front; shins) □21 Lower leg (back) □22 Achilles tendon

□23 Ankle □24 Heel □25 Foot/toe

□ other Other, namely ……….. 15. Which side of the body was injured?

□1 Left □2 Right □3 Both □0 Not applicable

16. What is the diagnosis? Multiple answers possible. □1 Bone fracture

□2 Other bone injury (e.g. stress fracture) □3 Joint dislocation/subluxation

□4 Joint inflammation (synovitis)

□5 Sprain/ligament injury (e.g. knee/ankle ligament) □6 Ligament rupture (e.g. knee or ankle ligament) □7 Lesion of meniscus or cartilage

□8 Muscle strain/tear □9 Muscle rupture □10 Muscle cramps

□11 Inflammation of a bursa (bursitis) □12 Tendinosis

□13 Tendon strain/tear □14 Tendon rupture

□16 Laceration/abrasion □17 Concussion

□18 Nerve injury □19 Dental injury □20 I don’t know yet

□other Other, namely ………

17. Please state the number of full days in the past four weeks that you completely/partly missed your dance/circus classes or activities due to your injury.

… days -> Go to question 21

18. Have you mentioned this mental complaint in the previous questionnaire? □0 No

□1 Yes

19. Which mental complaints did you experienced since the previous questionnaire? If several mental complaints occurred, please refer to the most severe one in the past four weeks. Other complaints can be filled in further down the questionnaire.

□1 General anxiety □2 Tension with people □3 Performance anxiety □4 Depression

□5 Stress due to external factors; e.g., bereavement (death of a beloved one), moving house

□6 Eating problems □7 Alcohol or drugs abuse □8 General low self-confidence □9 Sudden drop in self-confidence

□10 Consistent difficulty in concentrating in class or rehearsal □11 Constant tiredness

□12 Burn-out

□13 Feeling under pressure

□other Other, namely ……….

20. Please state the number of full days in the past four weeks that you completely/partly missed your dance/circus classes or activities due to your mental complaint.

… days

21. Have you experienced any (other) ‘physical’ injuries in the past four weeks?

□0 No -> Go to question 31

□1 Yes

22. Have you mentioned this injury in the previous questionnaire? □ 0 No

□ 1 Yes

23. Is the injury/complaint a recurrent one? □0 No, new

□2 It is still the same injury/complaint (not recovered in between) -> Go to question 26 24. Did your injury occur during dance/circus activities?

□1 Yes

□other No, injury occurred during: ……… 25. Is the injury caused by overuse or trauma? When we speak of ‘trauma’ this indicates an

injury that occurred suddenly. So there is a clear moment in time at which the injury occurred. This could also indicate an accident. We speak of 'overuse injuries', in case the injury occurred over a longer period of time.

□1 Trauma □2 Overuse

26. Which part of your body was injured? If several body parts were injured, please mention only one. Other injuries can be filled in further down the questionnaire.

□1 Head/face □2 Neck □3 Shoulder □4 Clavicle □5 Upper arm □6 Elbow □7 Forearm □8 Wrist □9 Hand/fingers/thumb □10 Chest (incl. organs) □11 Lower back (incl. coccyx) □12 Buttocks

□13 Abdomen (incl. organs) □14 Hip

□15 Groin

□16 Upper leg (front) □17 Upper leg (back) □18 Knee

□19 Upper back

□20 Lower leg (front; shins) □21 Lower leg (back) □22 Achilles tendon

□23 Ankle □24 Heel □25 Foot/toe

□other Other, namely ……….. 27. Which side of the body was injured?

□1 Left □2 Right □3 Both

□0 Not applicable

28. What is the diagnosis? Multiple answers possible. □1 Bone fracture