Both groups were allowed to eat as much as they wished using the macronutrient guidelines of the study; one group was taking in a “normal” amount of carbohydrates (60 percent of calories), the other consumed a “low” carbohydrate diet (30 percent). In just three days, the low-carbohydrate group saw a decrease in fT:C of 43 percent, the normal group saw only a 3 percent decrease, essentially unchanged.11 Though no difference in performance was measured between the two groups during the three days, one can reasonably assume that over time, the low-carbohydrate group would respond less well or even begin to suffer the effects of overtraining. Realize, this change occurred in the setting of a supplemented diet offering above maintenance calories.
The 43 percent reduction in fT:C surpasses the threshold considered to indicate a negative, catabolic state— 30 percent.13 These findings agree with the observation made by team dietitians who discourage athletes from following a low-carbohydrate diet during the pre-season or in season.14
The athlete and hardcore lifter are a results-oriented sub-population, measuring single percentile changes in performance or subtle improvements in physique over time. Extremely fitness conscious men are under additional pressure, needing to develop as lean a physique as possible. The need to lose body fat leads many to consume a hypocaloric diet, while maintaining a high rate of activity/training. Some athletes hold the benefit of using lipolytic and nutrient-partitioning drugs to funnel excess calories into energy or muscle mass. The drug-free athlete will restrict calories to the point of wasting, suffering losses in strength, muscle mass, energy, and mood. Often, carbohydrates are sacrificed protein calories to preserve lean mass.
Not surprisingly, the effect of a hypocaloric diet in a physically stressful setting is reflected hormonally. As with low-carbohydrate diets, the most relevant change is a reduction in the fT:C ratio. There is not much agreement in the literature, as the relatively few studies look at a diverse group of subjects: women with polycystic ovary syndrome; obese men; adolescents; endurance athletes; martial artists; etc. In males, hypocaloric diets tend to sway the metabolic balance toward catabolism. In some studies, this is due to a reduction in testosterone; others show an increase in cortisol and other hormones that release stored energy.15, 16
What recommendations can be made for serious lifters, seeking to reduce body fat without sacrificing muscle mass and strength? A group from the University of Arkansas for Medical Sciences proposed a diet very similar to that promoted for athletes in an article published in 2004.17 This diet suggests ingesting a hyper-energetic diet (more than maintenance calories) off-season, and a hypocaloric diet (15 percent below maintenance— roughly 500 calories per day) during pre-competition training, with a macronutrient ratio of 55-60 percent carbohydrate, 25-30 percent protein, and 15-20 percent fat.
Many hardcore lifters would find this to be too high in carbohydrates, particularly in the pre-competition phase. These guidelines are reasonable for the performance athlete, but for many others, it would not allow for a specific loss or management of body fat. Certainly, those seeking to gain mass in general, in the hopes of retaining lean mass gains, would benefit from increasing carbohydrates to these levels.
The anabolic effect of insulin released with such a diet would promote muscle mass. However, in the pre-competition phase, one would need to assess himself on an individual basis. If body fat is already low, and the goal is to maintain mass while gradually making a 3-5 percent decrease in body fat, a hypocaloric diet with prominent carbohydrate content near 55 percent may be optimal. However, for someone who needs to maximize and accelerate fat loss, even at the expense of some muscle mass and size, reducing carbohydrates below the level needed to avoid the threshold decrease in fT:C may be necessary.18
As noted earlier, when drug-free physique athletes began following a low-carbohydrate diet during the 8- 12 weeks pre-competition, the physiques became sharper and leaner. However, off-season, it makes little endocrinologic sense to maintain this protocol. During the pre-competition timeframe, athletes and lifters who follow a low-carbohydrate, low-calorie diet need to be aware of the potential for reduced strength, reaction, drive, and recovery.