Physical Activity

Physical activity is defined by the  World Health Organization (WHO) as "any bodily movement produced by skeletal muscles that requires energy expenditure" (1).

• Physical Activity Recommendations in Canada. It is recommended that adults enjoy at least 150 minutes of moderate to vigorous physical activity per week and children and youth enjoy at least 60 minutes on a daily basis.
• Health Benefits of Physical Activity. Participation in regular physical activity can improve health, help manage body weight and waist circumference, and reduce the risk of developing many chronic diseases. These benefits can be achieved as part of a balanced lifestyle that includes healthy eating.
• Carbohydrates for Healthy Active Living. Recommended intakes of carbohydrate is dependent on  amount and intensity of physical activity.
• Carbohydrates for Athletes and Sports Nutrition. There are specific carbohydrate recommendations for individuals/athletes who engage in high intensity exercise to ensure adequate supply of muscle glycogen and optimal performance.

Physical Activity Recommendations in Canada

Canadian 24-Hour Movement Guidelines for Adults Aged 18 – 64 Years  from the Public Health Agency of Canada and Canadian Society for Exercise Physiology recommend adults accumulate at least 150 minutes of moderate to vigorous intensity aerobic physical activity per week as well as several hours of light physical activities, including standing, per day (2). Older adults (65 years and over) should accumulate a similar amount and level of activity, however it is recommended that they also include physical activities that challenge balance (3).

For optimal health and development, Canadian 24-Hour Movement Guidelines for Children and Youth (ages 5-17 years) recommend children and youth engage in at least 60 minutes of moderate to vigorous physical activity daily, and limit recreational screen time to no more than 2 hours per day (4). Recent 24-Hour Movement Guidelines for the Early Years (ages 0-4) provide recommendations to achieve a balance of physical activity, high-quality sedentary behaviour, and sufficient sleep for infants, toddlers, and preschoolers (5).

Results from the 2014 and 2015 Canadian Health Measures Survey indicate that 1 in 5 (18%) of Canadian adults met the recommendation, while less than 1 in every 10 (8%) of children and youth met their recommended level of physical activity (6).

Health Benefits of Physical Activity 

Public Health Agency of Canada states that there are many health benefits to physical activity that extend beyond diet and weight maintenance (7). Regular physical activity plays a key role in preventing heart disease, stroke, diabetes, osteoporosis, and some cancers, and can help alleviate symptoms of depression. For children and youth, physical activity encourages optimal growth and development, and can help build positive self-esteem. For older Canadians, physical activity can help sustain independent living and can lead to improvements in quality of life. In general, by increasing the duration, intensity and/or frequency of physical activity, greater health benefits may be achieved.

Carbohydrates for Healthy Active Living

Carbohydrates, along with proteins and fats, are one of the main nutrients in our diets and provide the body with an essential source of energy (8). Adequate carbohydrate intake is essential for optimal performance in physically active individuals. The Dietary Reference Intake report recommends that all Canadians consume 45 to 65% of their total calories from carbohydrates, including grain products, fruits and vegetables, and legumes (9). The body can store energy from consumed carbohydrates as glycogen in the muscles and liver, but storage capacity is limited (e.g. liver glycogen is depleted after about 28 hours of fasting). Excess intake of carbohydrate beyond meeting the body’s daily normal energy requirement and supporting physical activity could be stored in the body as fat.

People who are very active (e.g. athletes) have particularly high carbohydrate requirements to ensure adequate fuel stores and optimal performance. During high-intensity exercise, the active muscle relies heavily on carbohydrate-derived energy sources (muscle and liver glycogen, blood glucose). Generally, consuming only water is sufficient for activities lasting less than 60 minutes, however very active Canadians or those exercising at a high intensity (e.g. athletes) may benefit from adjusting their intakes of energy and certain nutrients, such as carbohydrate based on their individual goals (10).  

Carbohydrates for Athletes and Sports Nutrition

It is the position of the Academy of Nutrition and Dietetics (AND), Dietitians of Canada (DC), and the American College of Sports Medicine (ACSM) that "physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition" (11).

Keeping carbohydrate stores adequately stocked is crucial for athletes who often need to perform at high exercise intensities (12, 13). Generally, as the energetic demands of training or competition increase so does the dietary carbohydrate requirement. The Figure below provides some general guidance for daily carbohydrate intake goals for athletes based on exercise context and intensity. When carbohydrate stores are inadequate athletes cannot meet the energy needs of the activities being performed, which can result in fatigue, reduced training ability, impaired performance, and reduced immune function.

For an in-depth overview of carbohydrate intake recommendations for athletes before, during, and post-exercise/performance, please see the factsheet “Role of Carbohydrates and Sugars in Sports Nutrition” authored by Dr. Gareth Wallis (University of Birmingham, UK).

For more information, additional resources include:  

• Online Learning Modules from Canadian Society for Exercise Physiology and Performance Nutrition Ltd - Sport Nutrition Education Series
• Infographic - Carbohydrates and Physical Activty
• Clips on Sugars - Fuel for Your Activity
• Carbohydrate News - Carbohydrate for Healthy Active Living
• Video - How Much Sugar is Too Much? featuring nutrition researcher Dr. Nick Bellissimo and registered dietitian Christy Brissette

Recent News Items Include: 

• April 2024 - New Learning Opportunity: Improve Athletic Performance Through Nutrition 

References

1. World Health Organization. Global Strategy on Diet, Physical Activity and Health. Geneva: World Health Organization; 2004 May 26. 
2. Canadian Society for Exercise Physiology. Canadian 24-Hour Movement Guidelines for Adults [Internet]. Ottawa: Canadian Society for Exercise Physiology; 2020 [cited 2024 Mar 4]. 
3. Canadian Society for Exercise Physiology. Canadian 24-Hour Movement Guidelines for Adults Aged 65 Years and Older [Internet]. Ottawa: Canadian Society for Exercise Physiology; 2020 [cited 2024 Mar 4].
4. Canadian Society for Exercise Physiology. Canadian 24-Hour Movement Guidelines for Children and Youth (ages 5-17 years) [Internet]. Ottawa: Canadian Society for Exercise Physiology; 2016 [cited 2024 Mar 4].
5. Canadian Society for Exercise Physiology. Canadian 24-Hour Movement Guidelines for the Early Years (0-4 years) [Internet]. Ottawa: Canadian Society for Exercise Physiology; 2017 [cited 2024 Mar 4].
6. Colley RC, Carson V, Garriguet D, Janssen I, Roberts KC, Tremblay MS. Physical activity of Canadian children and youth, 2007 to 2015. Health Rep. 2017;28(10):8-16.
7. Public Health Agency of Canada. Physical Activity [Internet]. Ottawa: Public Health Agency of Canada; 2015 Mar 27 [cited 2024 Mar 4].
8. Burke LM, Kiens B, Ivy JL. Carbohydrates and fat for training and recovery. J Sports Sci. 2004;22(1):15-30.
9. Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients). Washington: National Academy Press; 2005.
10. Kerksick CM, Arent S, Schoenfeld BJ, Stout JR, Campbell B, Wilborn CD, Taylor L, Kalman D, Smith-Ryan AE, Krieder RB, Willoughby D, Arciero PJ, VanDusseldorp TA, Ormsbee MJ, Wildman R, Greenwood M, Ziegenfuss TN, Aragon AA, Antonio J. International Society of Sports Nutrition position stand: Nutrient timing. J Int Soc Sports Nutr. 2017 Aug;14:33.
11. Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance. Med Sci Sports Exerc. 2016 Mar;48(3):543-68.
12. Potgieter S. Sport nutrition: A review of the latest guidelines for exercise and sport nutrition from the American College of Sport Nutrition, the International Olympic Committee and the International Society for Sports Nutrition. South Afr J Clin Nutr. 2013;26(1). 
13. Sports Nutrition Practice Guidance Summary. In: Practice-based Evidence in Nutrition [PEN]; 2017 Oct 24.