Two Studies: "Athletes: Eat Carbs."
With some of the carbophobia out there I wanted to post this. I have already received a question asking me how I could feel good about myself eating so many carbohydrates and I know many people who go on low-carb diets. To preface, these pieces of information were taken from the November 2010 issue of Muscular Development magazine, not some vegan-friendly source/propaganda. I am reprinting them in their entirety as they appeared in the magazine.
Muscle Recovery Impaired by Low-Carb Diets
The strongest and biggest guys in the gym recover quickly from training. Gaining strength and mass depends on training intensity. Athletes who can train hard and recover quickly without getting sick or injured make the most progress in their training programs.
Linda Lamont and colleagues from the University of Rhode Island found that post-exercise dietary carbohydrates, rather than proteins, were the most important nutrients for promoting recovery in novice weightlifters. They studied the effects of a five-day low-carbohydrate, higher-protein diet (3.4 grams carbohydrate per kilogram of body-weight; 1.5 grams protein/kg) or a high-carbohydrate, lower-protein diet (5.0 g/kg; 1.2g/kg) following 50 reps of knee extensions and flexions at 100 percent of maximum effort.
During recovery, the low-carbohydrate diet group showed a greater strength loss and reduced protein turnover, synthesis, and breakdown. Eat more carbs to speed recovery from intense weight training. (Journal of Exercise Physiology, online 12: 33-39, 2009)
Testosterone Sinks With Lower-Carb Diets
Testosterone is a highly anabolic hormone that maximizes gains in muscle mass and strength. Studies by Shalander Bhasin from Boston University showed that gains in muscle size were proportional to blood testosterone levels. Cortisol is a catabolic hormone that breaks down muscle tissue and increases the use of amino acids for fuel. Ideally, athletes want a high testosterone-to-cortisol ratio. Sophisticated sports medicine programs measure these hormones to help plan training and supplement programs.
Anthony Hackney and colleagues from the University of North Carolina found that a lower-carbohydrate (30 percent) diet, compared to a higher-carb (60 percent) diet, reduced the testosterone-to-cortisol ratio. In the lower-carb diet, the free testosterone dropped 36.1 percent and the cortisol increased by 14.8 percent!
Studies have shown that low-carb and ketogenic diets increase the stress hormone, cortisol. Intense exercise is a form of stress and in a glycogen-depleted state, will further exacerbate cortisol levels and enhance the suppression of testosterone.
Athletes should make sure they eat adequate amounts of carbohydrates on a daily basis, especially post-exercise, to enhance recovery from high-intensity training and to maintain optimum testosterone levels. (European Journal of Applied Physiology, in press; published online December 20, 2009)
