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In general, nutritional sports ergogenics are designed to enhance energy production and/or improve body composition, promoting muscle growth and decreasing body fat. Many of the nutritional supplements and pharmacological substances have been used during resistance training without knowledge about the effects on human metabolism caused by their chronic administration. Before the usage or prescription of any ergogenic aid, it is important to consider some questions about that substance: Is it effective? Is it safe? Is it legal and ethical? In this chapter we will discuss the most widely used drugs and supplements among individuals engaged in resistance training—testosterone, growth hormone and insulin growth factor-1, creatine, beta-hydroxy beta-methylbutyrate and caffeine—focusing on their effects on strength and body composition, the safety of their usage, and the mechanisms of action.

This study was carried out to evaluate the creatine and maltodextrine dietetic supplementation of eventing horses. The experimental period consisted of 56 days, with 20 horses, which were randomly divided into four groups with different diets. Diets were: diet without supplement (Control); diet supplemented with creatine, 44.4 mg/kg body weight/day (20 g creatine/horse/day); diet supplemented with creatine, 88.8 mg/kg body weight/day (40 g creatine/horse/day); diet supplemented with maltodextrine, 222.2 mg/kg body weight/day (100 g/horse/day), during three days before each test. Every horse was submitted to three tests. Blood samples and heart rate were collected at rest, immediately after the tests and 10 and 20 minutes after the test. Supplementation with creatine (44.4 mg/kg body weight/day) and maltodextrine reduced plasma concentration of lactate in horses during tests. Supplementation of creatine and maltodextrine did not alter serum concentration of aspartate aminotransferase, γ-glutamyltransferase, urea or creatinine, but training affected blood biochemical variables in eventing horses.

The benefits of creatine (CR) supplementation are well documented, particularly during repeated bouts of high-intensity muscular activity. Most published experiments use mass-supported (cycle ergometry) activities as a means of evaluating creatine's efficacy, therefore minimizing any possible adverse effects of increased body mass associated with CR supplementation. This study aims to use both mass-supported and mass-dependent activities to assess the effectiveness of acute CR supplementation on a group of highly trained rugby players. A randomized, double-blind, crossover research design was utilized, with subjects receiving 20 g.d(-1) x 5 d of both CR and a glucose placebo (PL). Subjects were assessed via 10 x 6-second Wingate test and a 10 x 40-m sprint test on separate days, presupplementation and postsupplementation. A 28-d washout period separated the two treatments. No significant treatment (p > 0.05) or treatment by test interaction effects (p > 0.05) were observed for peak or minimum power output (W), peak or minimum running velocity (m.s(-1)), or fatigue index (%). No significant differences (p > 0.05) were found postsupplementation for body mass and percentage body fat. Although statistical significance was not achieved for any of the measured parameters, there were small improvements in performance that may be of benefit to rugby players.

Because of the medium chain triglycerides (MCT) specific physical and chemical properties, they have been used over the last 40 years in enteral and parenteral nutrition. Results from clinical practice lead some researchers in the early 80's to use them for ergogenics purposes. The hypothesis was based on the relationship between the oxidation rates of carbohydrate and fat. The increase in fat oxidation would promote glycogen sparing effect, and therefore, delay the time to exhaustion. The aim of the present paper is to review the effects of MCT supplementation upon endurance exercise performance. Most of the studies failed to prove the ergogenic effect of MCT. A few studies that showed the ergogenic effect of MCT administration used alternative experimental designs, such as high MCT dose (above from the previous established limit) or infusion. The chronic use of MCT by athletes is new and few studies have been done in this matter. These few studies showed controversial results. There is a strong tendency in the literature that MCT is not a viable strategy to increase performance during endurance exercise. The aim of this study is to discuss the effects of MCT use on endurance exercise.

In general, nutritional sports ergogenics are designed to enhance energy production and/or improve body composition, promoting muscle growth and decreasing body fat. Many nutritional supplements and pharmacological substances have been used during resistance training without knowledge of the effects on human metabolism caused by their chronic administration. Before the utilization or prescription of any ergogenic aid, it is important to consider some questions about that substance: Is it effective? Is it safe? Is it legal and ethical? In this chapter we discuss the most widely utilized drugs and supplements among individuals engaged in resistance training—testosterone, creatine, beta-hydroxy beta-methylbutyrate (HMB) and caffeine—focusing on their effects on strength and body composition, the safety of their utilization, and their mechanisms of action.

The effect of creatine and caffeine supplementation on muscle torque generation and relaxation was investigated in healthy male volunteers. Maximal torque (Tmax), contraction time (CT) from 0.25 to 0.75 of Tmax, and relaxation time (RT) from 0.75 to 0.25 of Tmax were measured during an exercise test consisting of 30 intermittent contractions of musculus quadriceps (2 s stimulation, 2 s rest) that were induced by electrical stimulation. According to a double-blind randomized crossover design, subjects ( n = 10) performed the exercise test before (pretest) and after (posttest) creatine supplementation (Cr, 4 × 5 g/day, 4 days), short-term caffeine intake (Caf, 5 mg · kg−1 · day−1, 3 days), creatine supplementation + short-term caffeine intake (Cr+Caf), acute caffeine intake (ACaf, 5 mg/kg) or placebo. Compared with placebo, Cr shortened RT by ∼5% ( P < 0.05). Conversely, Caf increased RT (+∼10%, P < 0.05), in particular as RT increased because of fatigue. RT was not significantly changed by either Cr+Caf or ACaf. Tmax and CT were similar during all experimental conditions. Initial Tmax was ∼20% of voluntary maximal isometric contraction force, which was not different between treatments. It is concluded that Caf intake (3 days) prolongs muscle RT and by this action overrides the shortening of RT due to creatine supplementation.

A double-blind randomized study was performed to evaluate the effect of oral ribose supplementation on repeated maximal exercise and ATP recovery after intermittent maximal muscle contractions. Muscle power output was measured during dynamic knee extensions with the right leg on an isokinetic dynamometer before (pretest) and after (posttest) a 6-day training period in conjunction with ribose (R, 4 doses/day at 4 g/dose, n = 10) or placebo (P, n = 9) intake. The exercise protocol consisted of two bouts ( A and B) of maximal contractions, separated by 15 s of rest. Bouts A and B consisted of 15 series of 12 contractions each, separated by a 60-min rest period. During the training period, the subjects performed the same exercise protocol twice per day, with 3–5 h of rest between exercise sessions. Blood samples were collected before and after bouts A and B and 24 h after bout B. Knee-extension power outputs were ∼10% higher in the posttest than in the pretest but were similar between P and R for all contraction series. The exercise increased blood lactate and plasma ammonia concentrations ( P < 0.05), with no significant differences between P and R at any time. After a 6-wk washout period, in a subgroup of subjects ( n = 8), needle-biopsy samples were taken from the vastus lateralis before, immediately after, and 24 h after an exercise bout similar to the pretest. ATP and total adenine nucleotide content were decreased by ∼25 and 20% immediately after and 24 h after exercise in P and R. Oral ribose supplementation with 4-g doses four times a day does not beneficially impact on postexercise muscle ATP recovery and maximal intermittent exercise performance.

Vandenberghe, K., M. Goris, P. Van Hecke, M. Van Leemputte, L. Vangerven, and P. Hespel. Long-term creatine intake is beneficial to muscle performance during resistance training. J. Appl. Physiol. 83(6): 2055–2063, 1997.—The effects of oral creatine supplementation on muscle phosphocreatine (PCr) concentration, muscle strength, and body composition were investigated in young female volunteers ( n = 19) during 10 wk of resistance training (3 h/wk). Compared with placebo, 4 days of high-dose creatine intake (20 g/day) increased ( P < 0.05) muscle PCr concentration by 6%. Thereafter, this increase was maintained during 10 wk of training associated with low-dose creatine intake (5 g/day). Compared with placebo, maximal strength of the muscle groups trained, maximal intermittent exercise capacity of the arm flexors, and fat-free mass were increased 20–25, 10–25, and 60% more ( P < 0.05), respectively, during creatine supplementation. Muscle PCr and strength, intermittent exercise capacity, and fat-free mass subsequently remained at a higher level in the creatine group than in the placebo group during 10 wk of detraining while low-dose creatine was continued. Finally, on cessation of creatine intake, muscle PCr in the creatine group returned to normal within 4 wk. It is concluded that long-term creatine supplementation enhances the progress of muscle strength during resistance training in sedentary females.

Genetic endowment and proper training are the major factors contributing to athletic success in endurance and ultraendurance events. Proper nutrition, primarily adequate carbohydrate and fluid, prior to and during the event is also critical. Endurance athletes often utilize other nutritional substances or practices, often referred to as ergogenics, in attempts to obtain a competitive edge by enhancing energy utilization and delaying the onset of fatigue. Numerous nutritional ergogenics have been used in attempts to enhance endurance performance, but with several exceptions most have been shown to be ineffective, including bee pollen, L-carnitine, CoQ10, inosine, amino acids, alkaline salts, and vitamin E at sea level. Research findings are equivocal relative to the ergogenicity of caffeine, phosphate salts, and vitamin E at altitude. Loss of excess body fat, a nutritional practice, may be an effective ergogenic. Conversely, some agents such as alcohol may impair performance, an ergolytic effect. Additional research is necessary to support the efficacy of several nutritional ergogenics to enhance prolonged endurance performance, such as caffeine, phosphates, specific amino acids, and various commercial products. Such research should involve exercise tasks comparable in intensity and duration to that experienced in the marathon and similar endurance events.