Supplementation in bodybuilding

Supplementation in bodybuilding  became an essential part. Aggressive marketing has led millions of athletes to use dietary supplements. To cite only one example, a 1993 survey of the marketplace found 624 commercial products targeted to body builders, making more than 800 unsubstantiated health and performance claims. Many athletes take common vitamin and mineral supplements and may also take a wide variety of other less common supplements In spite of abundant evidence that bodybuilders’ nutrient needs can be met by well-balanced diets and that most supplements have no measurable effect on performance in well-nourished athletes, some athletes still take substantial quantities of supplements.

Supplement abuse can cause short-term acute symptoms such as nausea or diarrhea and long-term adverse effects such as nutrient imbalances or toxicity. Furthermore, some supplements contain substances banned by athletic governing bodies and some may contain impurities. Many clients do not think to report various supplements in a diet record or recall interview because supplements may not be considered food and they are often not consumed with meals. Bodybuilders may also be reluctant to disclose the use of some supplements, especially those that are prohibited by sports governing bodies. Information on the use of supplements must be  elicited by educated probing. The professional should be familiar with the range of supplements used by athletes in various sports and should develop a rapport with clients that will facilitate probing about the use of supplements, both the common vitamin and mineral preparations and the more exotic products targeted to athletes. identifies common supplement categories that athletes might use.

Protein Requirements for bodybuilding (resistance trained) athletes (IId part)

Protein Requirements for bodybuilding (resistance trained) athletes the first part.

 

It is apparent that, a meaningful recommendation for strength training athletes for a recommended dietary protein intake, based on the literature, is confounded by numerous factors including training status and combination of strength training with other modalities (sprint or aerobic exercise) and methodological considerations. What is certain, however, is that, even those athletes who have as their goal the gain of an impressive amount of lean mass, they do not require an enormous increase in protein intake.

Consequently, as with my recommendation for the dietary protein intake for endurance athletes, I believe that even the most ardent strength-training athletes need not consume any more than 15% of their dietary calories in the form of protein. These same athletes should, however, be getting at least 10% of their dietary energy from protein, so long as they are consuming sufficient protein to cover their energy needs or surfeit energy required for optimal weight gain. It should be emphasized that, for even for larger athletes (100 kg and greater); a sufficient energy intake to cover caloric requirements for weight gain during intense training may be in excess of 18MJ/d–1 (~4300 kcal). Hence, protein intakes as high as 20% of such an energy intake would mean a daily protein intake of 215g/d–1, which would definitely be excessive by any standard (2.15 g protein•kg–1•d–1). Hence, protein needs of this group of athletes generally should be balanced against what is onsidered necessary.

Protein Requirements for bodybuilding (resistance trained) athletes

Tarnopolsky and co-workers8 conducted a study using the nitrogen balance approach to examine the protein requirements of a group of bodybuilding -resistance trained athletes and a group of sedentary controls. As pointed out earlier, Tarnopolsky et al. have demonstrated that an isolated bout of resistance exercise did not increase leucine oxidation or perturb whole body protein turnover, likely because of the periodic recovery that occurs during a resistance vs. an endurance workout. Hence, it would appear that any extra protein required by strength-trained individuals is likely directed toward muscular hypertrophy in the earlier phases of training, when muscle mass is still increasing.

However, it should be stressed that, in highly trained powerlifters and bodybuilders, it is unlikely that dietary protein requirements are elevated much more than those of a sedentary person. In fact, any increase in protein requirements for such a highly trained group of individuals is likely only due to an increased rate of resting protein turnover. In support of the idea that training might induce an increase in resting muscle protein turnover, protein requirements of highly trained bodybuilders were found to be only 12% greater than those of sedentary controls, who had a protein requirement of 0.84 g protein•kg–1•d–1.8 The results of this study8 do highlight a puzzling result, however, that is evident in Figure 12.4. For example, on a protein intake (actually equivalent to the habitual protein requirement of bodybuilders) of ~2.8 g protein•kg–1•d–1, all bodybuilders were in highly positive nitrogen balance (~12-20 g N•d–1). When extrapolated back to actual protein, this would have meant that the bodybuilders should have gained ~ 300–500g of lean mass/d–1 (assuming muscle is 75% water and assuming that no other pool of body protein significantly increased in size), which obviously did not occur.8 The increasingly positive nitrogen balance, associated with higher protein intakes, that was observed in this8 and other7,117 studies is often incorrectly used to justify why high protein intakes are needed for resistance-trained athletes. Such shortcomings of nitrogen balance have long been recognized and have led to the recommendation of combining tracer and nitrogen balance approaches to determining protein requirements. Using a combination of nitrogen balance along with kinetic measurements of whole-body protein turnover, football and rugby players had protein requirements almost ~ 100% greater than those of a sedentary control group. In fact, onsumption of the low-protein diet (0.86 g protein•kg–1•d–1) by the strength trained group resulted in an accommodated state where whole body protein synthesis was reduced compared with the medium (1.4 g protein •kg–1•d–1) and high protein (2.4 g protein•kg–1•d–1) diets. In contrast to the results of Tarnopolsky et al., nitrogen balance studies conducted in the elderly have shown that initiating a moderate program of bodybuilding-strength training resulted in reduced protein requirements due to the anabolic stimulus of the resistance exercise. However, even following 10 weeks of comparatively mild resistance training, there was no evidence of muscle hypertrophy in people consuming either 0.8 or 1.6 g protein•kg–1•d–1. The results of Campbell et al. are remarkably similar to those reported by