The Caffeinated Athlete
Most research with caffeine is done with pure caffeine supplements. Does coffee offer the same ergogenic effect? Yes. In research with cyclists and triathletes, the time trial results were very similar with pure caffeine (39.4 minutes) and coffee (39.5 minutes). Instant decaffeinated coffee (41.4 minutes) gave the slowest time. The researchers suggest the small improvement was related to caffeine’s ability to stimulate the central nervous system. This makes exercise seem easier so the athlete can work harder.
An extensive review of the literature indicates caffeine does not have a dehydrating effect not impair heat tolerance. Hence, a 150-lb (68 kg) athlete need not worry about consuming about 200 to 600 mg caffeine (3-9 mg caffeine/kg body weight) when exercising in the heat. That’s 1 to 3 large cups of Joe.
More: 4 Ways to Stay Awake Without Coffee
While commonly consumed intakes of caffeine do not have a diuretic effect over the course of the 24-hour day, what happens in the short term? In three hours, habitual coffee drinkers who consumed 7 ounces (200 mL) coffee (with 250 mg caffeine) voided 11.3 ounces (316 mL) urine, very similar to the group that consumed plain water and voided 10.4 ounces (290 mL) urine.
When cyclists were given 1.5 or 3 mg caffeine/lb body weight (3-6 mg/kg) one hour prior to a 24-mile (40-km) time trial, they performed equally well, regardless of the dose. However, the athletes who responded best to pre-exercise caffeine had a specific gene that was missing in the non-responders. That is, when compared according to genotypes, the AA homozygote group was 4.6% faster at 6 mg caffeine/kg as compared to 2.6 percent improvement in the C allele carriers. Genetic differences influence caffeine’s ability to enhance exercise performance.
Is Red Bull better than coffee? Doubtful. In a cycling time trial, Red Bull enhanced performance similarly to caffeine. Red Bull's added ingredients offered no additional benefits.
More: Give Your Workout a Caffeine Kick
Bone Health and Body Fat
Female cyclists who trained about 10 hours a week had low spine bone density in the osteopenic range—even though they were only 26 years old! Whether you are male or female, if you spend most of your exercise-time cycling, think about cross training with weight bearing exercise to improve your bone health.
When getting your body fat measured with a Bod Pod, be sure to follow the instructions to not eat, drink, or exercise for two hours before the measurement. Athletes who did 30 minutes of treadmill exercise prior to Bod Pod testing were 21.3 percent body fat pre-exercise and 19.6 percent post-exercise. That 2 percent drop was not due to a loss of body fat, but rather to inaccuracy related to having an elevated body-temperature!
More: Understand Your BMI and Body Fat Percentage
When getting your body fat measured, take note: Different methods of body fat measurement give different results. In collegiate gymnasts, the body fat results were:
Omron HBF-510W 26.1% fat ($55 on amazon.com)
Tanita BF-350 21.7% ($899 at Walmart)
Tanita BF-522 21.7% ($366 at amazon.com)
DXA 21.06% (research-based; the “gold standard”)
Omron HBF-306C 18.4% ($30 on amazon.com)
Trained runners lost twice as much sweat during a one-hour summer race than they had predicted. As a group, they predicted losing about 750 mL sweat in hot, humid conditions but they actually lost about 1,500 ml. Weigh yourself pre/post exercise to learn your sweat rate.
More: Measure Your Sweat Loss for Optimal Hydration
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