Basic cycling nutrition.
Three basic calorie-containing components: carbohydrate,
fat, protein (and alcohol, depending on who you talk to).
- Carbohydrate = 4
calories/gram
- Fat = 9 calories/gram
- Protein = 4 calories/gram
- Alcohol = 7 calories/gram
During moderate exercise (~60%of VO2max or less) the body
uses ~50% carbohydrates and 50% fat/protein. During intense exercise (>~80%
VO2 max), the body uses carbohydrate almost exclusively ? the only substrate
that can provide energy quickly enough. We store ~500 grams (~2000 calories) of
carbohydrate in our bodies as glycogen; when we?ve depleted all the glycogen
during intense exercise, we ?hit the wall? or ?bonk.?
We also rely on many other factors, including water and electrolytes, to
provide the optimal environment for the chemical reactions of nutrition and
muscle contraction to take place. These, too, are depleted during exercise.
By optimizing carbohydrate, water, and electrolyte delivery to muscle, we can
provide the right amount of ?fuel? for the muscles and the right environment
for the muscles to work during intense exercise.
Lower intensity training diet should consist of:
- ~60% carbohydrate (~6 grams
per kg of body weight)
- 12-15% protein
- 30% or less fat
Higher intensity training diet should consist of:
- 65-70% carbohydrate (8-10
grams per kg of body weight)
- 12-15% protein
- 20% or less fat
Carbohydrates and exercise
- 1-4 grams of carbohydrate per
kg of body weight 1-4 hours before event.
- 30-60 grams of carbohydrate
(120-240 calories) per hour during event.
Hydration and exercise
- Start hydrated ? lots of
fluids in the 24 hours prior to event, avoid excessive alcohol/caffeine.
- 500-750 ml per hour ? 5-10
ounces every 15-20 minutes, or one large water bottle per hour.
- If event is greater than one
hour, should use an electrolyte-containing energy drink that has between 6
and 10% carbohydrate (% carbohydrate = grams carbohydrate/ml of fluid x
100).
After exercise
- The body is primed to replace
spent glycogen most efficiently immediately after exercise.
- Having 1 gram of carbohydrate
pound of body weight within 30 minutes of finishing exercise and again 2-4
hours later will replenish the majority of glycogen within 24 hours ?
crucial if training intensely/racing several days in a row.
*Low carbohydrate diets have been shown repeatedly to impair
endurance performance.
Supplements ? 10 questions that put supplements to the test (from Serious
Cycling by Ed Burke, Ph.D.)
- What scientific evidence is
available to support the claim?
- Where were the scientific
studies conducted?
- By whom? What were the
researchers? and laboratories? qualifications?
- Do the researchers have a
commercial or financial interest in the company?
- Where was the study
published? Was it a reputable scientific journal or a magazine?
- Was the study peer reviewed?
- Are there any other studies
to support or deny the claims?
- What do recognized experts in
the field say about the research?
- Who are the experts? What are
their credentials?
- Do the experts have a financial
interest in the product?