What are Canada’s recommendations for physical activity for adults aged 18-64?
• At least 150 min of moderate to vigorous intensity
activity/week
• Add up activities in periods of at least 10 minutes
• 2 days/week: muscle and bone strengthening activities
Explain how fuel use varies at rest, in the early minutes of activity and as activity continues
At rest:
- ½ fatty acids, other ½ mostly glucose, some AAs
During activity:
- Early minutes: majority from muscle glycogen
- As activity continues: glucose and FAs
What are some diet strategies to maintain CHO concentrations?
- Eat high CHO diet daily
- Take in some glucose during activity
- Eat CHO-rich foods within ~2 hours post activity (boosts muscle glycogen stores)
- CHO loading:
> moderate activity followed by high CHO intake
What are the recommendations for fat intakes for athletes?
20-30% calories from fat
What are the recommendations for protein intake for athletes?
Protein needs
> Higher for endurance & strength athletes
> No benefit beyond 1.6g/kg per day
Eating protein with CHO <2 hours post activity:
> Can enhance muscle protein synthesis
> CHO rich diet spares protein from being used as fuel
Discuss the role of vitamin and mineral supplements in athletic performance
- Do not enhance performance if well nourished
- Can help if athlete is deficient
What benefits do sports drinks have for athletes?
Benefits for activity >60 min. Contains electrolytes and maintains blood glucose levels
What is the role of complete meal replacers for athletes?
- Marketed as “complete” meals, but often fall short
- Calories often from fat & sugars
- Good for athletes with “pre-game jitters” unable to tolerate solid food on day of event
- Should not be used as sole source of nutrients – hard to meet high nutrient needs
What are ergogenic aids?
- supposedly enhance performance
- many are regulated, some are banned
- most are not proven to be effective
- many have serious side effects
Describe amino acid supplements
- made for building muscles
- extra AAs do not necessarily cause more muscle growth
- a well-balanced diet provides enough AAs to build muscles
What are some side effects of caffeine?
Dehydration, stomach upset, irritability, constriction of arteries ~> ⬆️HR ~> ⬆️work for the heart
- Could be detrimental to sports performance
What is carnitine?
Non-essential nutrient needed by our cells to transport fat molecules across the mitochondrial membrane. This is used to advertise the claim that carnitine increases fat burning. There is no evidence of this
What is creatine?
Some scientific evidence exists that it enhances performance during intense activity, but many studies show NO such effect
Creatine metabolism leads to production of the toxin formaldehyde: long-term safety unknown
May cause kidney damage
