© 2002

Nutrition expert answers commonly-asked questions...

Question:

What superficially appears to be a simple question is actually quite complex. The true need for a daily vitamin can really be assessed only on an individual basis. Several variables such as diet, geography, activity level, exposure to light, exposure to toxins, concurrent consumption of foodstuffs that may hamper absorption, and age all may determine whether a person could benefit from a daily vitamin. Other considerations include dieting for weight loss, lactose intolerance, food allergies, vegetarianism, and pregnancy.

I have followed the debate over taking vitamin and mineral supplements as "health insurance" for a number of years. For me, it’s been like watching a tennis match, with one argument being served and effectively returned by the opponent. Let’s be realistic; true nutritional deficiencies in modernized societies is rare. Do you know anyone who was admitted to a hospital for complications stemming from a nutrient deficiency? Probably not. However, I do believe that many persons may have a marginal vitamin and mineral intake. For readers of this publication, the question really is not a matter of preventing deficiency but rather it is about creating a physiological environment that allows optimal adaptation to the demands of exercise. Really, I quit concerning myself over this issue because in otherwise healthy persons, no vitamin or mineral exhibits toxicity at modest levels above the recommended intake. What harm will a conservative daily vitamin and mineral supplement do? Such supplementation is simple and inexpensive.

We insure our cars, our loved ones, our homes, our pets... Why not spend a few cents a day to insure our bodies? It is unlikely that the addition of a daily vitamin and mineral supplement has ever been detrimental to anyone’s training progress, unless perhaps someone choked to death on one. For the very frugal or cautious, they can consume such a supplement every-other-day. Nevertheless, because a vitamin supplement cannot cure all that ails one’s dietary habits, it is most ideal to implement the use of a nutrient supplement after consulting with a qualified nutritionist who can thoroughly analyze your typical dietary intake.

In my own statistical analysis of the effects of resistance training on protein needs (as assessed by nitrogen balance), there was no significant interaction between total training time and nitrogen balance. In layman’s terms, it appears that training duration does not positively or negatively influence protein requirements for optimal muscle mass increases. This makes sense given some facts.

First, in the vast majority of studies, multiple sets of resistance exercise (i.e., higher volume) have neither proven inferior nor superior to single sets regarding lean body mass increases or strength. Thus, there should be no reason that more protein is required of either high-volume or low –volume trainees if increases in lean body mass are the same. Second, it is well established that protein does not contribute considerably to the energy needs of athletes except for extreme endurance athletes. So, although high-volume trainees may expend more energy during a training session, only a few grams of protein may be catabolized to meet energy demands. Third, the net amount of protein consumed between workouts probably does not affect protein needs because consuming tons of protein will not upregulate the rate at which muscle protein synthesis occurs. Despite what additional tissue damage a high-volume trainee may inflict, the body is very efficient at recycling damaged proteins.

To paraphrase, I do not believe there is sufficient evidence to conclude that low-volume and high-volume trainees have greatly different protein requirements for optimal muscle mass accretion. For more on this topic, see the article "Protein for Your Routine" at this site.

Dr. Greg Bradley-Popovich holds dual master's degrees in Exercise Physiology and Human Nutrition from West Virginia University as well as a doctorate in Physical Therapy from Creighton University. He is the Director of Clinical Research at Northwest Spine Management, Rehabilitation, and Sports Conditioning in Portland, Oregon.