Page 1, 2, Notes
Whey protein is rich in essential AAs and contains high amounts of sulfur-containing AAs (e.g., cysteine), glutamine, and BCAAs. It is a popular meal replacement for athletes due to its high biological value.
Whey protein supplies cysteine needed for the synthesis of glutathione, the body's main antioxidant.57 Any supplement that can aid the body's endogenous production of antioxidants probably plays a role in lessening damage and speeding recovery from exercise.58,61 Glutathione levels are reduced during exercise.59 Ultraendurance events, such as marathons and triathlons, can increase oxidized glutathione levels by 189%.60
Whey enhances body levels of cysteine, taurine, glutamine, and BCAAs, among others. This can have consequences in several areas, including immune function.60-63 Nothing can interrupt training more than illness.
Whey protein also has merit as a fat-loss and muscle-building aid, which may make it useful as a preworkout meal compared with carbohydrate, which may slow fat loss.64 Whey protein also shows a powerful ability to regulate hunger and binge eating for weight control.65 A study by Akhavan et al. showed that whey protein taken before an all-you-can-eat pizza meal significantly lowered food intake, postmeal glucose, and insulin levels in response to the meal.66
Whey protein can provide benefit when timed appropriately with exercise. Whey protein postworkout may be one of the most beneficial things that one can do to maximize lean body mass. Whey protein is low glycemic but insulinogenic at the same time.66,67 This may create a unique opportunity for muscle growth without fat gain, especially in a postworkout setting.
The addition of a small amount of carbohydrate may be more beneficial in terms of muscle gain. In studies analyzing postworkout intake of protein alone, carbohydrate alone, or a combination of both, protein and carb together generates the greatest insulin response. This enhances muscle glycogen synthesis and storage and has benefit for athletes in terms of recovery.68,69 Adding fat to the mix is not beneficial and may blunt this response.70
Combining whey protein and creatine may have synergistic benefit. Men supplementing their diets with a combination of whey protein and creatine together (1.2 g/kg/day of whey with 0.1 g/kg/day creatine) enjoyed greater improvements in strength and muscle mass compared with placebo.71
While many people are dairy intolerant, whey seems to be handled well by most. It has low levels of lactose, and tends to be digested easily.
Dosages tend to be the following: preworkout 5 to 10 g, postworkout 25 to 50 g, and meal replacement 15 to 30 g.
Conjugated Linoleic Acids (CLA)
CLA is a family of isomers of linoleic acid found mostly in beef, lamb, and dairy. Studies in the past have been confusing because different mixtures of isomers of CLA appear have to different biological effects. According to a 2013 review by Filippo et al., supplementing with CLA may help with fat loss and preserve lean mass when CLA is combined with resistance training.72-75 Recent research also indicates that CLA may increase testosterone levels.75
Ingesting glycerol with water appears to prevent dehydration by enhancing hydration status during prolonged exercise, thus enabling the athlete to perform longer and more efficiently.76,77 Unfortunately, glycerol has the potential to mask blood doping, and as a result has recently been added to the World Anti-Doping Agency's (WADA) prohibited list.78
The above natural substances have preponderance of evidence relative to other nutraceuticals indicating they are either "apparently effect" or "possibly effective" for enhancing athletic performance.2 Most of these natural ergogenic aids are considered legal in international sports competition, with the exception of glycerol. Some athletic organizations, such as the NCAA, have also banned caffeine above a certain level in the urine.79
As natural health-care providers, our goal is to assist our patients and clients in optimizing their health. The closer one gets to optimal health on the health continuum, the more likely one will perform better in life and in athletic competition. Many nutritional supplements appear to enhance athletic performance that are not discussed above. However, in most cases, research has not caught up with the many other athletic performance aids being used in the field. An ergogenic aid is defined as any external influence that aids in athletic performance beyond what a sufficiently healthy person can do. That kind of definition still leaves much room for debate.
email@example.com | firstname.lastname@example.org
Page 1, 2, Notes