Canadian Science Publishing sponsors the Applied Physiology, Nutrition, and Metabolism Undergraduate Research Excellence Awards, which are awarded in partnership with the Canadian Society for Exercise Physiology and the Canadian Nutrition Society. Award winner Robyn Madden shares her research on nutrition of athletes with physical disabilities.

By Robyn Madden

In May 2015, I was presented with the opportunity to enter the field of nutritional research under the supervision of Dr. Jill Parnell in the Department of Health and Physical Education at Mount Royal University. Dr. Parnell has an interest in sports nutrition and dietary supplementation habits in young athletes. Her interests have expanded to researching sports nutrition and dietary supplementation in elite athletes with physical impairments. This led to our research study titled Evaluation of Dietary Intakes and Supplement Use in Paralympic Athletes.

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Missing links in nutrition research

The Paralympic games are highly competitive and athletes need to optimize their performance. One aspect of performance optimization is nutrition. Although there has been considerable research on nutrition in able-bodied athletes, specialized recommendations for athletes with physical impairments are not available¹. As well, dietary intakes and dietary supplement use (e.g., vitamins, protein powder) in elite Canadian athletes with physical disabilities remains unexplored. The lack of credible nutrition and supplement information for this population is alarming as these athletes are at risk for nutritional deficiencies and supplement misuse.  

The overarching goal of this study was to assess nutritional intakes, dietary supplementation patterns, and sources of dietary supplement information in Canadian athletes with physical disabilities. Specifically, we sought to:

1. Quantify nutrient intakes from food and beverages in athletes with physical disabilities. 
2. Identify common nutrient deficiencies or excesses in athletes with physical disabilities. 
3. Determine the types and frequency of dietary supplements being used by athletes with physical disabilities. 
4. Identify what sources athletes with physical disabilities utilize most for nutrition and dietary supplement information. 
5. Identify what sources athletes with physical disabilities prefer to utilize for nutrition and dietary supplement information. 

Getting data on diets: how we did it

Forty male and female athletes over the age of 18 with physical or visual disabilities as set out by the International Paralympic Committee² were recruited from nine Paralympic sports through sporting organizations, coaches, and social media (Facebook and Twitter posts). 

Athletes interested in participating were instructed to email the researchers after seeing recruitment information either through social media or hearing about it from their coaches. 
Participants were sent a copy of the dietary supplement questionnaire that was designed to collect information on the types and frequencies of use of dietary supplements. The questionnaire also asked participants which sources of information they use to learn about supplements. Participants were required to record all foods and beverages consumed over the course of three consecutive days. The food and beverage records provided information on the participants’ dietary intake of macronutrients (e.g., carbohydrates, fats) and micronutrients (e.g., vitamins, minerals). Participants were encouraged to provide as many details about the foods and beverages as possible including size, brand, flavor, and method of cooking.

Physically impaired athletes have adequate diets, commonly use supplements  

Athletes with physical disabilities had diets that were adequate in macronutrients. On average, males had greater total energy intakes than females (male = 2092 kcal/day; female = 1602 kcal/day). Carbohydrate intakes based on body weight (BW) were similar in both genders (male = 3.5 g/kg/BW, female = 3.4 g/kg/BW). For some athletes, carbohydrate intake was below sport-specific recommendations; emphasizing higher carbohydrate intake may be necessary for these athletes. However, carbohydrates should be monitored since an increase in carbohydrate consumption may lead to weight gain if it results in excessive calories³. Fat intakes were similar in both genders, while males had slightly greater protein intakes. 

Although athletes met or exceeded the recommended daily allowance for most micronutrients, of concern was that both genders were severely lacking in vitamin D intakes (males = 35.5%, females = 19%). Vitamin D is important for bone-building⁴ and muscle strength, mass, and functioning⁵. A deficiency in vitamin D may lead to various health problems including rickets, osteoporosis, and osteomalacia⁶. Emphasizing vitamin D supplementation may be viable in this population. 

Recommended iron intakes were not met in the majority of female athletes. Iron deficiency can promote anemia, which may result in weakness, fatigue, poor concentration, and decreased physical performance^7-9. Female athletes possess a higher risk of iron deficiencies than males due to losses from menses and lower overall energy intakes⁷. Female athletes in this population may benefit from iron supplementation. 

All male athletes and 80% of female athletes reported using supplements. The most common supplements used on a regular basis were vitamin D, protein powder (e.g., whey isolate), protein or sport bars (e.g., protein-dense bar), sport or electrolyte drink/supplement, fatty acid preparations (e.g., flax seed oil), and multivitamin/mineral pill. 

The top three reasons for taking dietary supplements were “stay healthy”, “increase energy”, and “medical.” 

When asked the question “Where do you get information about dietary supplements?” athletes ranked their top three sources as dieticians, medical doctors, and athletic trainers. When asked “Which way do you prefer to receive information about dietary supplements?” athletes preferred individual nutrition consultation, coach or athletic trainer, and medical doctor.

Evidence-based recommendations still needed 

Elite Canadian athletes with physical disabilities demonstrated a high usage of supplements designed for health and performance. However, with no current recommendations on supplement use and nutritional needs for these athletes, it is exceedingly difficult for nutrition professionals to assess and advise them. 

This study highlighted the need for tailored recommendations for energy, macronutrient, and micronutrient intakes. Increased carbohydrate intakes should be emphasized depending on the severity of macronutrient impairment. Supplementation is generally not required, with the possible exception of iron for females and vitamin D for both genders. 

We hope the current study will help establish nutritional and dietary supplement guidelines for physically impaired athletes as well as help sport nutrition professionals educate these athletes. Future research that focuses on the development of recommendations and educational interventions to help optimize these athletes’ nutritional health and performance is urgently required. 

—

References

¹Risk of nutrient inadequacies in elite Canadian athletes with spinal cord injury

²IPC Policy on Eligible Impairments in the Paralympic Movement 

³Nutritional practices of competitive British wheelchair games players

⁴Eating attitudes and food intakes of elite adolescent female figure skaters: a cross sectional study

⁵Vitamin D and skeletal muscle function in athletes

⁶Vitamin D deficiency in individuals with a spinal cord injury: a literature review

⁷Dietary intakes and supplement use in pre-adolescent and adolescent Canadian athletes

⁸Iron-deficiency anemia

⁹Iron deficiency in athletes: an update

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Robyn Madden graduated with a Bachelor of Health and Physical Education and a Bachelor of Business Administration from Mount Royal University in Calgary, Alberta. She has presented her findings twice at the Canadian Nutrition Society conference. Robyn is currently working on her MSc in kinesiology under the supervision of Dr. Jane Shearer at the University of Calgary in the area of nutrition, metabolism, and genetics. 

Canadian Science Publishing sponsors the Applied Physiology, Nutrition, and Metabolism Undergraduate Research Excellence Awards, which are awarded in partnership with the Canadian Society for Exercise Physiology and the Canadian Nutrition Society. Award winner Robyn Madden shares her research on nutrition of athletes with physical disabilities.

By Robyn Madden

In May 2015, I was presented with the opportunity to enter the field of nutritional research under the supervision of Dr. Jill Parnell in the Department of Health and Physical Education at Mount Royal University. Dr. Parnell has an interest in sports nutrition and dietary supplementation habits in young athletes. Her interests have expanded to researching sports nutrition and dietary supplementation in elite athletes with physical impairments. This led to our research study titled Evaluation of Dietary Intakes and Supplement Use in Paralympic Athletes.

—

Missing links in nutrition research

The Paralympic games are highly competitive and athletes need to optimize their performance. One aspect of performance optimization is nutrition. Although there has been considerable research on nutrition in able-bodied athletes, specialized recommendations for athletes with physical impairments are not available¹. As well, dietary intakes and dietary supplement use (e.g., vitamins, protein powder) in elite Canadian athletes with physical disabilities remains unexplored. The lack of credible nutrition and supplement information for this population is alarming as these athletes are at risk for nutritional deficiencies and supplement misuse.  

The overarching goal of this study was to assess nutritional intakes, dietary supplementation patterns, and sources of dietary supplement information in Canadian athletes with physical disabilities. Specifically, we sought to:

1. Quantify nutrient intakes from food and beverages in athletes with physical disabilities. 
2. Identify common nutrient deficiencies or excesses in athletes with physical disabilities. 
3. Determine the types and frequency of dietary supplements being used by athletes with physical disabilities. 
4. Identify what sources athletes with physical disabilities utilize most for nutrition and dietary supplement information. 
5. Identify what sources athletes with physical disabilities prefer to utilize for nutrition and dietary supplement information. 

Getting data on diets: how we did it

Forty male and female athletes over the age of 18 with physical or visual disabilities as set out by the International Paralympic Committee² were recruited from nine Paralympic sports through sporting organizations, coaches, and social media (Facebook and Twitter posts). 

Athletes interested in participating were instructed to email the researchers after seeing recruitment information either through social media or hearing about it from their coaches. 
Participants were sent a copy of the dietary supplement questionnaire that was designed to collect information on the types and frequencies of use of dietary supplements. The questionnaire also asked participants which sources of information they use to learn about supplements. Participants were required to record all foods and beverages consumed over the course of three consecutive days. The food and beverage records provided information on the participants’ dietary intake of macronutrients (e.g., carbohydrates, fats) and micronutrients (e.g., vitamins, minerals). Participants were encouraged to provide as many details about the foods and beverages as possible including size, brand, flavor, and method of cooking.

Physically impaired athletes have adequate diets, commonly use supplements  

Athletes with physical disabilities had diets that were adequate in macronutrients. On average, males had greater total energy intakes than females (male = 2092 kcal/day; female = 1602 kcal/day). Carbohydrate intakes based on body weight (BW) were similar in both genders (male = 3.5 g/kg/BW, female = 3.4 g/kg/BW). For some athletes, carbohydrate intake was below sport-specific recommendations; emphasizing higher carbohydrate intake may be necessary for these athletes. However, carbohydrates should be monitored since an increase in carbohydrate consumption may lead to weight gain if it results in excessive calories³. Fat intakes were similar in both genders, while males had slightly greater protein intakes. 

Although athletes met or exceeded the recommended daily allowance for most micronutrients, of concern was that both genders were severely lacking in vitamin D intakes (males = 35.5%, females = 19%). Vitamin D is important for bone-building⁴ and muscle strength, mass, and functioning⁵. A deficiency in vitamin D may lead to various health problems including rickets, osteoporosis, and osteomalacia⁶. Emphasizing vitamin D supplementation may be viable in this population. 

Recommended iron intakes were not met in the majority of female athletes. Iron deficiency can promote anemia, which may result in weakness, fatigue, poor concentration, and decreased physical performance^7-9. Female athletes possess a higher risk of iron deficiencies than males due to losses from menses and lower overall energy intakes⁷. Female athletes in this population may benefit from iron supplementation. 

All male athletes and 80% of female athletes reported using supplements. The most common supplements used on a regular basis were vitamin D, protein powder (e.g., whey isolate), protein or sport bars (e.g., protein-dense bar), sport or electrolyte drink/supplement, fatty acid preparations (e.g., flax seed oil), and multivitamin/mineral pill. 

The top three reasons for taking dietary supplements were “stay healthy”, “increase energy”, and “medical.” 

When asked the question “Where do you get information about dietary supplements?” athletes ranked their top three sources as dieticians, medical doctors, and athletic trainers. When asked “Which way do you prefer to receive information about dietary supplements?” athletes preferred individual nutrition consultation, coach or athletic trainer, and medical doctor.

Evidence-based recommendations still needed 

Elite Canadian athletes with physical disabilities demonstrated a high usage of supplements designed for health and performance. However, with no current recommendations on supplement use and nutritional needs for these athletes, it is exceedingly difficult for nutrition professionals to assess and advise them. 

This study highlighted the need for tailored recommendations for energy, macronutrient, and micronutrient intakes. Increased carbohydrate intakes should be emphasized depending on the severity of macronutrient impairment. Supplementation is generally not required, with the possible exception of iron for females and vitamin D for both genders. 

We hope the current study will help establish nutritional and dietary supplement guidelines for physically impaired athletes as well as help sport nutrition professionals educate these athletes. Future research that focuses on the development of recommendations and educational interventions to help optimize these athletes’ nutritional health and performance is urgently required. 

—

References

¹Risk of nutrient inadequacies in elite Canadian athletes with spinal cord injury

²IPC Policy on Eligible Impairments in the Paralympic Movement 

³Nutritional practices of competitive British wheelchair games players

⁴Eating attitudes and food intakes of elite adolescent female figure skaters: a cross sectional study

⁵Vitamin D and skeletal muscle function in athletes

⁶Vitamin D deficiency in individuals with a spinal cord injury: a literature review

⁷Dietary intakes and supplement use in pre-adolescent and adolescent Canadian athletes

⁸Iron-deficiency anemia

⁹Iron deficiency in athletes: an update

---

Robyn Madden graduated with a Bachelor of Health and Physical Education and a Bachelor of Business Administration from Mount Royal University in Calgary, Alberta. She has presented her findings twice at the Canadian Nutrition Society conference. Robyn is currently working on her MSc in kinesiology under the supervision of Dr. Jane Shearer at the University of Calgary in the area of nutrition, metabolism, and genetics.