Dietary sport supplements have gained tremendous popularity in the last several decades and are now an established part of the landscape of modern sport.
However, some athletes who take supplements have no clear understanding of the potential effects. This includes the benefits and any potential risks associated with the product. Before deciding to use any supplement, the risks and rewards need to be weighed.
Most recently, the International Olympic Committee published a consensus statement on dietary supplements in The British Journal of Sports Medicine (1). Authored by leading researchers in the field of sports nutrition, the statement warned against taking these products without weighing the risks and benefits associated with their consumption. In some circumstances, products can be a waste of money while others may cause serious harm.
Approximately half of the adult U.S. population uses some form of dietary supplement (2). In athletes, the level of prevalence is thought to be even higher (3). Surveys of athletes generally indicate that supplement use varies across different sports and activities, increases with level of performance and age, and is higher in men than in women (3).
Rewards could include correction of nutrient deficiencies, achievement of nutritional goals, or performance enhancement. While risks could include inappropriate use of supplements, such as consuming too much or taking at an inappropriate time. A more ominous type of risk that is generally unbeknownst to the athlete is contamination and adulteration.
The biggest concern for athletes who compete under an anti-doping code (usually the World Anti-Doping Code, as published by WADA) is that supplements can contain prohibited substances that result in an anti-doping rule violation. This includes products containing ingredients on the Prohibited List (WADA.ama.org.).
Supplements that contain prohibited substances as an undeclared ingredient or contaminants continue to be a problem with some reports, estimating up to 15 percent of sports products sold worldwide containing undeclared ingredients (4).
The range of prohibited substances found as undeclared ingredients in supplements now includes products from many sections of WADA’s List of Prohibited Substances and Methods, including stimulants, anabolic agents, selective androgen receptor modulators, and diuretics (5).
Athletes who use products that are Informed-Sport Certified ensure that the products are safe for sport and noncontaminated. Informed-Sport screens for more than 160 substances that have been banned in sport and may pose a threat in terms of product contamination. Isagenix has ensured all AMPED™ products carry this certification. For more information, see Informed-Sport.com.
Another way to ensure supplement security is to use products with an established track record for safety and efficacy. Supplements that directly and/or indirectly improve sports performance, with a strong evidence base that supports their use as safe, legal, and effective is a must. The IOC names ingredients including caffeine, creatine, nitrates, beta-alanine, vitamin D, vitamin C, carbohydrate, polyphenols, zinc, glutamine, omega-3 fatty acids, and beta-glucans (1). Protein is the premier ingredient in sports supplements especially when combined with resistive exercise (6). All the above ingredients are found in Isagenix products, reflecting our commitment to science and safety.
- Maughan RJ, Burke LM, Dvorak J et al. IOC consensus statement: dietary supplements and the high-performance athlete. Br J Sports Med. 2018 Apr;52(7):439-455.
- Bailey RL, Gahche JJ, Lentino CV et al. Dietary supplement use in the United States, 2003-2006. J Nutr. 2011 Feb;141(2):261-6.
- Knapik JJ, Steelman RA, Hoedebecke SS et al. Prevalence of Dietary Supplement Use by Athletes: Systematic Review and Meta-Analysis. Sports Med. 2016 Jan;46(1):103-23.
- Geyer H, Parr MK, Koehler K et al. Nutritional supplements cross-contaminated and faked with doping substances. J Mass Spectrom. 2008 Jul;43(7):892-902.
- Martínez-Sanz JM, Sospedra I, Ortiz CM et al. Intended or Unintended Doping? A Review of the Presence of Doping Substances in Dietary Supplements Used in Sports. Nutrients. 2017 Oct 4;9(10).
- Hector AJ, Phillips SM. Protein Recommendations for Weight Loss in Elite Athletes: A Focus on Body Composition and Performance. Int J Sport Nutr Exerc Metab. 2018 Feb 19:1-8.
Break Through Performance Plateaus With Creatine
Similar to plateaus that happen with weight loss, athletes also see them with sport, particularly in resistance training.
The reality is that the more experience a person has with exercising, the more difficult it is to make progress (1, 2). For this reason, many studies that investigate sports supplements do so in untrained individuals, yet the results from these products may not be applicable to more seasoned athletes.
Creatine might be the exception to the rule. According to a newly published research report, the supplement taken daily demonstrated that it could lead to increases in muscle mass even in experienced resistance trained men (3).
Creatine for 12 Weeks in Experienced Weight Lifters
Sport scientists randomized 45 men who were experienced with resistance training into two groups: one that received slightly above 2 grams of creatine and one that received a placebo. They carried out the study over 12 weeks with pre- and post-testing that consisted of anthropometric and body composition measurements.
With guidance from a dietitian, the subjects maintained their usual dietary intake throughout the intervention period. They also participated in a resistance training program. Results? The subjects who supplemented with creatine saw significantly increased muscle mass over the placebo group with the greatest effects seen in the upper limbs. The authors speculated that the difference in muscle mass response in the upper versus the lower limbs may be due to the muscle fiber composition. For example, there’s generally a higher percentage of fast-twitch fibers in the upper compared to lower-body muscles (4).
Takeaway: Creatine Works Even for Seasoned Athletes
Creatine may offer a way to increase performance in those more experienced athletes. The reason is that it accelerates the rate of restoring cellular energy during and after exercise (5-7). What this means for the athlete is greater strength, less fatigue, and a shorter recovery period (5-7).
Another way that creatine might work is by leading to an increase in intracellular water (8). That increased cellular hydration may contribute to greater muscle building by stimulating pathways that increase protein synthesis and suppressing those involved in protein degradation (9).
Note that similar to the dosage of creatine used in this study, both Isagenix AMPED™ Nitro and AMPED Power each contain 3 grams of highly pure creatine monohydrate in the form of the branded ingredient Creapure®. The two products are also Informed Sport-certified to ensure that every batch is tested for harmful and World Anti-Doping Agency (WADA) banned substances.
- Ahtiainen JP, Pakarinen A, Alen M et al. Muscle hypertrophy, hormonal adaptations and strength development during strength training in strength-trained and untrained men. Eur J Appl Physiol. 2003 Aug;89(6):555-63.
- Deschenes MR, Kraemer WJ. Performance and physiologic adaptations to resistance training. Am J Phys Med Rehabil. 2002 Nov;81(11 Suppl): S3-16.
- Nunes JP, Ribeiro AS, Schoenfeld BJ et al. Creatine supplementation elicits greater muscle hypertrophy in upper than lower limbs and trunk in resistance-trained men. Nutr Health. 2017 Dec;23(4):223-229.
- Sjøgaard G. Capillary supply and cross-sectional area of slow and fast twitch muscle fibres in man. Histochemistry. 1982;76(4):547-55.
- Bemben MG, Lamont HS. Creatine supplementation and exercise performance: recent findings. Sports Med. 2005;35(2):107-25.
- Branch JD. Effect of creatine supplementation on body composition and performance: a meta-analysis. Int J Sport Nutr Exerc Metab. 2003 Jun;13(2):198-226.
- Lanhers C, Pereira B, Naughton G et al. Creatine Supplementation and Upper Limb Strength Performance: A Systematic Review and Meta-Analysis. Sports Med. 2017 Jan;47(1):163-173.
- Powers ME, Arnold BL, Weltman AL et al. Creatine Supplementation Increases Total Body Water Without Altering Fluid Distribution. J Athl Train. 2003 Mar;38(1):44-50.
- Schoenfeld BJ. Potential mechanisms for a role of metabolic stress in hypertrophic adaptations to resistance training. Sports Med. 2013 Mar;43(3):179-94.
Strength Training Benefits Don’t Just Come from the Gym
When people think about exercising for health, the first thing that comes to mind is typically cardio exercises and lifting heavy weights at the gym.
However, as research is emerging on the benefits of strength training, new findings suggest that the advantages that come with strength training can happen outside a gym, using body weight exercises, for example.
Reductions in blood pressure, blood lipids, and blood glucose are all benefits of regular strength training (1). There’s evidence that the improvements seen are at least as significant as aerobic exercise. Yet, while the recommendations are to engage in at least two strength training episodes per week, researchers estimate only 9 percent of adults meet the recommendations (2).
In a recent study, published in the American Journal of Epidemiology, researchers followed up with more than 80 thousand adults, recruited over 30 years (3). The average length of follow-up was nine years. Researchers were interested in strength training exercise and how often, if at all, individuals participated in strength or resistance training exercises. They then calculated the risk of death according to how much and how often they exercised.
As it turns out, it doesn’t matter if strength training exercises are completed in a gym or in another setting so long as strength and resistance exercises were completed through the week. Adults who worked out in a gym averaged 60 minutes per week, while those working at home using body weight exercises averaged 50 minutes per week. Those who usually completed their training sessions in a gym reported using free weights or weight machines while those who worked out in other locations, their home or a park for example, primarily used body weight exercises. Not all participants met the guidelines for aerobic activity, but it turns out that had little effect on the overall results.
Participation in any form of strength training exercise was associated with a 31 percent lower risk of cancer mortality and a 23 percent lower risk of all-cause mortality – independent of whether the person met aerobic guidelines as well – versus adults who did not regularly participate in any form of strength training.
The results of this study are very encouraging for anyone who wants to work out at home or forego lifting the traditional weights and use the machines at the gym. Just incorporating an hour of strength training through the week is enough to promote health benefits.
A good way to incorporate an hour of resistance training each week is by using the PRISE protocol developed by Paul Arciero, Ph.D. Strength training is part of Dr. Arciero’s recommended program, as the “R” stands for resistance training. Sessions should be approximately an hour long and consist of a dynamic warmup, footwork and agility exercises, lower and upper body resistance exercises, and core exercises. Exercises should cause muscular fatigue in 10-15 repetitions for 2-3 sets. Participants should take a 30-second rest between sets and a 60-second rest between different exercises.
- Westcott WL. Resistance training is medicine: effects of strength training on health. Curr Sport Med Rep. 2012 Jul/Aug; 11(4): 209-216. doi: 1249/JSR.0b013e31825dabb8.
- Kraschnewski JL, Sciamanna CN, Poger JM, et al. Is strength training associated with mortality benefits? A 15 year cohort study of US older adults. Prev Med. 2016 Jun; 87: 121-127. doi: 10.1016/j.ypmed.2016.02.038.
- Stamatakis E, Lee I, Bennie J, et al. Does strength promoting exercise confer unique health benefits? A pooled analysis of eleven population cohorts with all-cause, cancer, and cardiovascular mortality endpoints. Am J Epidemiol. 2017 Oct 31. doi: 10.1093/aje/kwx345.
Why Taurine Is Safe and Helps Athletic Endurance and Recovery
Taurine is a natural organic acid that’s central to normal human physiology and found in plentiful amounts in the human body. In fact, it makes up about a gram per kilogram of body weight and is found mainly in the brain, eyes, heart, reproductive organs, and skeletal muscle.
A normal diet typically contains between 40- to 400-milligrams of taurine per day, coming from foods such as poultry, beef, pork, and seafood (2, 3). Taurine is also a conditionally essential amino acid, meaning we can make it in our own bodies provided we have the appropriate levels of methionine and cysteine.
For athletes, taurine supplementation is also linked to improved performance. Most recently, a meta-analysis of studies performed by researchers from the University of New England, in Armidale, Australia, and St. Mary’s University in London found that daily intake of a single dose of taurine in varying amounts could lead to better endurance performance (4).
The researchers based their findings on 10 different peer-reviewed studies, including a subanalysis of time-to-exhaustion trials (4). In these studies, a range of subjects including athletes used taurine doses of anywhere from one to six grams per day in single doses for up to two weeks (4). Taurine’s effects on endurance performance didn’t appear to depend on dose or whether taken short term or long term.
Among the reasons why taurine is linked to improved performance is through its protection against the effects of oxidative stress during exercise. It’s thought to enhance exercise capacity due to its cell-protective properties, and some researchers also believe there are synergistic effects of caffeine and taurine that further improve performance.
Separately, caffeine and taurine have each demonstrated safety and efficacy (5-7). However, in recent years the question has arisen over the safety and efficacy of caffeine and taurine when consumed together.
Most of the concerns are related to energy drink consumption, particularly in those containing high levels of caffeine, taurine, and other stimulatory ingredients such as high doses of caffeine-containing guarana. Additional concerns arise when energy drinks are combined with alcohol ingestion, used in those with sleep deprivation, and used among contraindicated populations such as pregnant women, children, and those with pre-existing cardiac disorders (6-9).
Beyond when used inappropriately, claims of negative health effects are generally unsubstantiated (6, 10). For example, the European Food Safety Authority concluded that the exposure to taurine presently used in energy drink products is not of safety concern and an interaction between either caffeine or taurine is unlikely (11). Like creatine, due to its historical use in combinations with steroids or dangerous stimulants, taurine and caffeine have been simply characterized as “guilty by association.”
In 2014, scientists reviewed the physiological functions of taurine and found that they were inconsistent with the adverse cardiovascular symptoms associated with excessive consumption of caffeine-taurine containing beverages (11). Previously, the European Union’s Scientific Committee on Food published a report in March 2003 summarizing its investigation into potential interactions of the ingredients in energy drinks. At the cardiovascular level, they concluded that “if there are any interactions between caffeine and taurine, taurine might reduce the cardiovascular effects of caffeine” (11).
Several studies have involved heavy taurine supplementation that demonstrated no safety concerns or serious adverse effects. While the largest dosage of taurine tested in humans appears to be 10 grams per day for six months, (12) several studies have used one to six grams per day for periods of one week to a year (6).
Reviewing the literature, consuming caffeine and taurine under moderate use and without combining other stimulants or alcohol is completely safe. Although it’s important to mention that many serious health risks that have been associated with energy drinks were due to overconsumption of the products or their ingestion in a short period (10). Pregnant women, children, and those with underlying illnesses such as hepatic failure or cardiomyopathy should likely avoid these types of products.
AMPED™ Nitro contains a dose of 100 mg of caffeine with 500 mg of taurine. Based on the scientific literature, this dosage and combination is safe and effective for improving performance. We encourage that the drink be used as intended— one or up to two servings daily to boost workout performance.
- Huxtable RJ. Physiological actions of taurine. Physiol Rev. 1992 Jan;72(1):101-63.
- Laidlaw SA, Grosvenor M, Kopple JD. The taurine content of common foodstuffs. JPEN J Parenter Enteral Nutr. 1990 Mar-Apr;14(2):183-8.
- Spriet LL, Whitfield J. Taurine and skeletal muscle function. Curr Opin Clin Nutr Metab Care. 2015 Jan;18(1):96-101.
- Waldron M, Patterson SD, Tallent J, Jeffries O. The effects of an oral taurine dose and supplementation period on endurance exercise performance in humans: A meta-analysis. Sports Med. 2018 Mar 15. doi: 10.1007/s40279-018-0896-2
- Heckman MA, Weil J, Gonzalez de Mejia E. Caffeine (1, 3, 7-trimethylxanthine) in foods: a comprehensive review on consumption, functionality, safety, and regulatory matters. J Food Sci. 2010 Apr;75(3): R77-87.
- Shao A, Hathcock JN. Risk assessment for the amino acids taurine, L-glutamine and L-arginine. Regul Toxicol Pharmacol. 2008 Apr;50(3):376-99.
- Al-Shaar L, Vercammen K, Lu C et al. Health Effects and Public Health Concerns of Energy Drink Consumption in the United States: A Mini-Review. Front Public Health. 2017 Aug 31; 5:225.
- Seifert SM, Seifert SA, Schaechter JL et al. An analysis of energy-drink toxicity in the National Poison Data System. Clin Toxicol (Phila). 2013 Aug;51(7):566-74.
- Wesensten, NJ. Legitimacy of concerns about caffeine and energy drink consumption. Nutr Rev. 2014 Oct;72 Suppl 1:78-86.
- Wassef B, Kohansieh M, Makaryus AN. Effects of energy drinks on the cardiovascular system. World J Cardiol. 2017 Nov 26;9(11):796-806.
- Schaffer SW, Shimada K, Jong CJ et al. Effect of taurine and potential interactions with caffeine on cardiovascular function. Amino Acids. 2014 May;46(5):1147-57.
- Durelli L, Mutani R, Fassio F. The treatment of myotonia: evaluation of chronic oral taurine therapy. Neurology. 1983 May;33(5):599-603.
How Athletes Lost Weight, Kept Muscle, and Improved Performance with Partial Intermittent Fasting
In a variety of sports, athletes often seek to lose weight while keeping muscle for a competitive advantage. For example, these can include athletes in any form of fitness competition, bodybuilding, or even combat sports like wrestling or judo.
The problems of athletes who attempt to diet is that, as they restrict food calories, most of the time they also risk losing muscle and hindering their performance.
But through use of a special dietary protocol developed by sport scientists from the Olympic Training Center in Barcelona, new research suggests that athletes can succeed in keeping muscle and improving their performance through a calorie restriction program that was achieved through every-other-day bouts of intermittent partial fasting (1).
“After six weeks of participating in a caloric restriction program based on intermittent partial fasting, athletes’ physical performance was enhanced,” the researchers wrote in the Journal of the International Society of Sports Nutrition (1). The athletes lost a modest amount of weight by the end of the study, primarily related to a significant, 15 percent reduction in body fat. Despite the modest weight loss, the athletes’ lean body mass was only reduced by less than 3 percent.
They also saw significant improvement in physical performance parameters. These included lower heart rate, lactate levels, and fatigue perception. By the end of the study, in fact, the athletes improved their energy expenditure while running by 10 percent.
Essentially, these results show that the fasting intervention promoted a more efficient use of energy when carrying out physical activity. The authors theorized these improvements could be explained by improved efficiency of mitochondria, the energy-producing structures inside cells (2).
Combining Higher Protein with Intermittent Fasting
The study included 12 healthy male athletes who trained between three and six times per week. The participants reduced energy intake by 30 to 40 percent with respect to their usual diet by alternating three fasting days with four normal eating days per week for six weeks.On average, the participants consumed 77 grams of protein per day or approximately 1 gram of protein per kilogram bodyweight. While the scientists did observe minor decreases in lean body mass, they noted that this reduction “could probably be avoided by increasing protein intake to around 2.3 grams per kilogram of body weight or by supplementing the diet with branched-chain amino acids that maintain lean mass while promoting the loss of fat mass.”
Increasing protein intake for athletes is a well-established method to offset muscle loss during times of caloric restriction, and may offer another component to maintaining or improving performance during fasting (3). In two separate performance studies that involved Isagenix products, for example, men and women consuming 2 grams of protein per kilogram body weight, including quality protein from Isagenix products, saw significant improvements in muscular performance (4, 5).
The researchers also noted that the intervention significantly reduced the athletes’ daily vitamin and mineral intake, leading to values lower than recommended dietary allowances for athletes. This reduction was most apparent for iron, niacin, riboflavin, pyridoxine, and vitamins A and D. If maintained over a longer period, low vitamin and mineral intake could compromise athletic performance. To prevent micronutrient deficiency, the researchers suggested that including vitamin and minerals supplements should be considered.
The study also suggests that athletes could find similar performance benefits when employing Isagenix-style Cleanse Days. These could also be combined with a modified protocol on Shake Days with high-protein IsaLean Pro Shakes, appropriate calorie intake to fuel performance, and supplementation with Complete Essentials Daily Pack to avoid micronutrient deficiencies.
- Pons V, Riera J, Capo X et al. Calorie restriction regime enhances physical performance of trained athletes. J Int Soc Sports Nutr. Mar 2018; 15(12). [Epub]
- López-Lluch G, Hunt N, Jones B et al. Calorie restriction induces mitochondrial biogenesis and bioenergetic efficiency. Proc Natl Acad Sci U S A. 2006 Feb 7;103(6):1768-73.
- Mettler S, Mitchell N, Tipton KD. Increased protein intake reduces lean body mass loss during weight loss in athletes. Med Sci Sports Exerc. 2010 Feb;42(2):326-37.
- Arciero PJ, Ives SJ, Norton C et al. Protein-Pacing and Multi-Component Exercise Training Improves Physical Performance Outcomes in Exercise-Trained Women: The PRISE 3 Study. Nutrients. 2016 Jun 1;8(6). pii: E332.
- Ives SJ, Norton C, Miller V et al. Multi-modal exercise training and protein-pacing enhances physical performance adaptations independent of growth hormone and BDNF but may be dependent on IGF-1 in exercise-trained men. Growth Horm IGF Res. 2017 Feb; 32:60-70.