Do Low Carbohydrate Diet Help or Hinder Muscle and Strength Gains? by Jerry Brainum 4/22

The debate continues about whether consuming a low carbohydrate diet will hinder muscle and strength gains. Much of the research that shows the importance of carbohydrates for exercise are based on studies that have involved endurance athletes. This is important because endurance athletes have far different energy needs compared to those who engage in resistance exercise. The primary fuel for both strength training and endurance training is glycogen, a form of carbohydrate stored in the liver and muscle. But it's the glycogen stored in the muscle that plays a major role in energy support for exercise and sports. Endurance training, especially long-distance events, such as marathons, result in a marked depletion of existing glycogen stores. As such, it's vital for endurance athletes to ingest a larger amount of carbohydrates. When endurance athletes deplete most of their existing muscle glycogen stores, it's as if the energy switch that controls muscle is turned off. Years ago, when knowledge of sports nutrition was in its infancy, you would often see marathon and other long-distance runners fall apart during the later stages of a running event. This was termed "hitting the wall" and involved a failure of the muscles to function due to near-complete depletion of existing muscle glycogen stores. This is rarely seen today because the knowledge of nutrition has increased to the point where most athletes and their coaches know how to properly fuel for an upcoming race. For endurance athletes, this means loading up on carbohydrates.

Because of the success is shown by endurance athletes who consume large amounts of carbohydrates, various "experts" decided that those who do not engage in endurance events but do lift weights several times a week should likewise also consume large amounts of carbohydrates. The reasoning involved the fact that similarly to endurance training, weight-training exercise also was fueled primarily by stored muscle glycogen, and the best way to replenish depleted muscle glycogen stores following training was to consume copious amounts of carbohydrates. While no one argues that muscle glycogen is indeed the primary fuel for anaerobic exercises, such as typical bodybuilding training, the notion that bodybuilders and others involved in weight-training need to ingest as many carbohydrates as endurance athletes never made any sense, yet was the typical advice offered by "sports nutrition experts." However, it's faulty reasoning if for no other reason than those who engage in bodybuilding or fitness workouts never deplete their muscle glycogen stores in a manner comparable to endurance athletes. Those who are not insulin insensitive, referring to a failure of insulin to properly adjust blood glucose levels, can ingest large amounts of carbohydrates without any obvious problems. But for the approximately 75% of the population that is insulin insensitive, ingesting too many carbohydrates will not only not provide any advantages, but will promote a gain of body fat.

Recently there has been a notable backlash against the idea that an excessive intake of carbohydrates can . . .