Search

It is well documented that exercise-induced muscle damage (EIMD) decreases exercise performance by elevated inflammation and subjective discomfort. Due to its potent antioxidative properties, astaxanthin (AX) may serve as a potential dietary supplement strategy for mitigating delayed-onset muscle soreness (DOMS) and enhancing recovery and performance. This study aimed to investigate the effects of AX on markers of muscle damage, inflammation, DOMS, and anaerobic performance and substrate metabolism. Thirteen resistance-trained men (mean ± SD, age, 23.4 ± 2.1 years) completed a double-blind, counterbalanced, and crossover design with a 1-week washout period between 2, 4-week supplementation periods at 12 mg·d-1 of AX or placebo. After each supplementation period, subjects completed 2 trials, with trial 1 including a graded exercise test (GXT) and a 30-second Wingate and trial 2 including an EIMD protocol followed by the collection of fasting blood samples (pre-post) to measure creatine kinase, advanced oxidative protein products, C-reactive protein, interleukin-6, insulin, and cortisol. Astaxanthin supplementation had no statistical effects on markers of substrate metabolism during the GXT, Wingate variables, or markers of muscle damage, inflammation, or DOMS when compared with placebo (all p > 0.05). However, 4 weeks of AX supplementation did significantly lower oxygen consumption during the final stage of the GXT (12%, p = 0.02), as well as lowered systolic blood pressure (~7%, p = 0.04), and significantly lowered baseline insulin values (~24%, p = 0.05) when compared with placebo. Collectively, these data suggest that 4 weeks of AX supplementation at 12 mg·d-1 did not affect markers of muscle damage, inflammation, or DOMS after an EIMD protocol in a resistance-trained male cohort. [ABSTRACT FROM AUTHOR]

Fazio, C, Elder, CL, and Harris, MM. Efficacy of alternative forms of creatine supplementation on improving performance and body composition in healthy subjects: a systematic review. J Strength Cond Res 36(9): 2663–2670, 2022—Novel forms of creatine have appeared in the marketplace with substantial claims of improved efficacy compared to creatine monohydrate (CrM). The purpose of this study was to conduct a systematic review on alternative forms of creatine to determine (a) whether they are effective ergogenic aids and (b) whether they outperform CrM. A separate comparison was conducted to determine average cost of various forms of creatine. Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Medline, and Google Scholar were systematically reviewed according to PRISMA guidelines. The design of the review was set to answer the PICOS model (subjects, interventions, comparators, outcomes, and study design). Seventeen randomized placebo controlled clinical trials examining exercise performance outcomes and body composition were included in the analysis. Magnesium-creatine chelate and creatine citrate, malate, ethyl ester, nitrate, and pyruvate were the only forms researched in the literature. Of these studies, only 3 studies compared the alternative creatine form to CrM, making it difficult to compare efficacy to CrM. There were no consistent findings of performance enhancement among alternative forms of creatine when compared to placebo. A review of the marketplace shows that CrM is the lowest cost form of creatine. Due to the paucity of studies on alternative forms of creatine as well as high prices on the market of these alternative forms, CrM remains as the most extensively studied form of creatine that shows efficacy, safety, and lowest cost to consumer. [ABSTRACT FROM AUTHOR]

McLester, CN, Bailey, P, Bechke, EE, Williamson, CM, McLester, JR, and Kliszczewicz, B. The effects of caffeine and Citrus aurantium on performance during repeated maximal anaerobic exercise bouts in habitual caffeine users. J Strength Cond Res 35(12): 3394-3399, 2021-The combination of caffeine (CAF) and Citrus aurantium (CA) have demonstrated the potential to improve various types of performance. To date, few studies have explored this relationship in purely anaerobic-based exercise. Therefore, the purpose of this study was to examine the influence of an acute dose of CAF + CA on peak anaerobic performance and the attenuation of power over multiple anaerobic bouts and to determine any differences in perceived effort or fatigue. Ten active men (25.1 +/- 3.9 years) who habitually consumed caffeine volunteered to perform repeated anaerobic bouts on a cycle ergometer on 2 separate days, consuming either a placebo or 100 mg CAF + 100 mg CA. Significance was set at p <= 0.05 and repeated measures analysis of variance showed no main effects for peak power p = 0.520, mean power p = 0.926, minimum power p = 0.321, total work p = 0.924, time to peak power p = 0.536, or rate of fatigue p = 0.284. There was a time effect for all variables (p <= 0.05) with the exception of time to peak power (p = 0.181). There were no differences in any measures of perceived effort or fatigue between conditions (p >= 0.05), but there were time-dependent differences observed each day (p <= 0.05). Overall, an acute dosage of 100 mg CAF and 100 mg CA did not elicit any differences in anaerobic performance or in perceived measures of effort and fatigue in young males who habitually consume caffeine. Therefore, caution should be used when pairing CAF and CA for the goal of improving anaerobic performance, because no clear benefit was realized in this population at this dosage. /=>/p> [ABSTRACT FROM AUTHOR]

Carbohydrate-protein-based supplements have been proposed for maximizing postexercise recovery. This study compared the effects of postworkout supplementation ingesting a multi-ingredient (MTN) vs. carbohydrate alone (CHO) on the recovery of muscle function and perceived of delayed onset of muscle soreness (DOMS) after hard resistance workouts. In a double-blinded, crossover design, 10 resistance trained men (26.9 ±7.4 years) performed 2 identical 5-day intervention periods while ingesting either MTN or CHO. The subjects performed one workout per day during the first 3 days. Thereafter, they were assessed 1, 24, and 48 hours after the completion of the third workout session. Primary outcome was tensiomyography (muscle displacement [Dm], contraction time [Tc], and contraction velocity [Vc]) of the vastus medialis (VM) and biceps femoris long head (BFLH). Secondary outcomes were performance and DOMS. At 24 hours, both conditions decreased (p<0.05)Dm(MTN21.7161.8, CHO21.586 1.46 mm) and Vc (MTN 20.03 ±0.03, CHO 0.03 ±0.04 m·s-1) in the VM. At 48 hours, all tensiomyography variables were recovered under the MTN while remained depressed (p, 0.01) in CHO (VM, Dm 1.616 1.60, Vc 20.046 0.04m·s-1; BFLH, Dm 1.54 ±1.52, Vc 20.02 ±0.02 m·s-1). Vertical jump performance decreased in CHO, but not in MTN. Although both conditions decreased upper-body strength and power at 1 hour, values returned to baseline in 24 hours for MTM while needed 48 hours in CHO. DOMS similarly increased at both 24 and 48 hours in both conditions. Compared with the ingestion of only carbohydrates, postworkout multi-ingredient supplementation seems to hasten recovery of muscular contractile properties and performance without attenuating DOMS after hard resistance workouts. [ABSTRACT FROM AUTHOR]

L-citrulline (CIT) is a nonessential amino acid that is touted as an ergogenic aid for athletic performance because of its purported ability to stimulate nitric oxide production. Although previous research has demonstrated that CIT supplementation over a period of days improves physiological factors such as V[Combining Dot Above]O2 kinetics, no studies to date have explored whether there is a direct benefit to endurance performance. This study used a randomized, double-blind, crossover design to test whether chronic supplementation with pure CIT improves cycling performance over a maltodextrin placebo (PLAC). Nine trained male cyclists (24 ± 3 years; 181 ± 7 cm; 76 ± 13 kg; 4.18 ± 0.51 L·min V[Combining Dot Above]O2max) completed two 7-day supplementation periods (6 g·d of CIT or PLAC) separated by a 7-day washout. Subjects consumed the final 6-g dose 2 hours before the cycling performance evaluation, which consisted of a 40-km time trial (TT) followed by a supramaximal sprint repeat task (SRT). Paired t-tests and repeated-measures analysis of variance (α = 0.05) were used to analyze TT and SRT data, respectively. CIT supplementation produced an improvement in TT time of 5.2% that trended toward significance (p = 0.08). Furthermore, CIT promoted a significant increase in average heart rate, average rating of perceived exertion, and average power throughout the TT (p < 0.05). However, supplementation with CIT did not prevent fatigue during the SRT. Overall, this study is the first to demonstrate that CIT supplementation may provide a modest improvement to endurance cycling performance in trained athletes. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the acute effect of capsaicin supplementation on performance, rate of perceived exertion (RPE), and blood lactate concentrations during short-duration running in physically active adults. Ten physically active men (age = 23.5 ± 1.9 years, mass = 78.3 ± 12.4 kg, and height = 177.9 ± 5.9 cm) completed 2 randomized, double-blind trials: Capsaicin condition (12 mg) or a placebo condition. Forty-five minutes after supplement consumption, the participants performed a 1,500-m running time trial. Time (in seconds) was recorded. Blood lactate concentration was analyzed at rest, immediately after exercise, after 5, 10, and 30 minutes during recovery and the RPE was collected after exercise. The time was significantly (t = 3.316, p = 0.009) lower in the capsaicin (371.6 ± 40.8 seconds) compared with placebo (376.7 ± 39 seconds). Rate of perceived exertion was significantly (t = 2.753, p = 0.022) less in the capsaicin (18.0 ± 1.9) compared with the placebo (18.8 ± 1.3). Lactate increased across time for both conditions without significant differences between (p > 0.05). In summary, acute capsaicin supplementation improves middle distance running (1,500 m) performance and reduced RPE in physically active adults. [ABSTRACT FROM AUTHOR]

Caffeine can reduce muscle pain during exercise; however, the efficacy of caffeine in improving muscle soreness and recovery from a demanding long-duration exercise bout has not been established. The purpose of this study was to investigate the effects of caffeine intake on ratings of perceived muscle soreness (RPMS) and perceived lower extremity functionality (LEF) following the completion of a 164-km endurance cycling event. Before and after cycling RPMS (1-to-6; 6 = severe soreness) and LEF (0-to-80; 80 = full functionality) were assessed by questionnaires. Subjects ingested 3 mg/kg body mass of caffeine or placebo pills in a randomized, double-blind fashion immediately after the ride and for the next 4 mornings (i.e., ~800 hours) and 3 afternoons (i.e., ~1200 hours). Before each ingestion, RPMS and LEF were assessed. Afternoon ratings of LEF were greater with caffeine ingestion the first day postride (65.0 ± 6.1 vs. 72.3 ± 6.7; for placebo and caffeine, respectively; p = 0.04), but at no other time points (p > 0.05). The caffeine group tended to have lower overall RPMS in the afternoon versus placebo (i.e., main effect of group; 1.1 ± 0.2 vs. 0.5 ± 0.2; p = 0.09). Afternoon RPMS for the legs was significantly lower in the caffeine group (main effect of caffeine; 1.3 ± 0.2 vs. 0.5 ± 0.3; p = 0.05). In conclusion, ingesting caffeine improved RPMS for the legs, but not LEF in the days following an endurance cycling event. Athletes may benefit from ingesting caffeine in the days following an arduous exercise bout to relieve feelings of soreness and reduced functionality. [ABSTRACT FROM AUTHOR]

The article discusses research on how citrulline malate supplementation can influence exercise performance, heart rate, and blood pressure of advanced weightlifters during lower-body resistance exercise. It explores the use of this supplement by athletes to enhance muscle performance, the citrulline malate dosage ingested by study participants prior to the exercise protocol outlined, and a comparison between exercise performance of groups that received either placebo or citrulline malate.

Research is presented that investigated the effect of acute L-carnitine supplementation on the endurance performance of 26 professional football players. The study found that their running speeds corresponding to specific lactate (La) concentrations increased while La and heart rate responses to running speeds decreased in the supplemented groups. It also shows that exhaustion was prolonged when a specific amount of L-carnitine was taken before physical exercise.

The article reports on research which was conducted to investigate the effect beta-alanine supplementation had had on high-velocity intermittent running. Researchers evaluated 50 recreationally trained runners. They found that the supplementation had no ergogenic effect on critical velocity, anaerobic running capacity or time to exhaustion in the runners.

The article presents the results of a study which investigated the usefulness of a sublingual spray as an ergogenic aid. The experimental protocol included tests of grip strength, vertical jumping and bench press repetitions. It was found that the spray improved bench pressing performance, but not the jump or grip tests.

The purpose of this case study was to examine the effects of repeated creatine administration on muscle phosphocreatine, plasma creatine, and urine creatine. One male subject (age, 32 years; body mass, 78.4 kg; height, 160 cm; resistance training experience, 15 years) ingested creatine (20 g-d-1 for 5 days) during 2 bouts separated by a 30-day washout period. Muscle phosphocreatine was measured before and after supplementation. On day 1 of supplementation, blood samples were taken immediately before and hourly for 5 hours following ingestion of 5 g of creatine, and a pharmacokinetic analysis of plasma creatine was conducted. Twenty-four-hour urine collections were conducted before and for 5 days during supplementation. Muscle phosphocreatine increased 45% following the first supplementation bout, decreased 22% during the 30-day washout period, and increased 25% following the second bout. There were no meaningful differences in plasma creatine pharmacokinetic parameters between bouts 1 and 2. Total urine creatine losses during supplementation were 63.2 and 63.4 g during bouts 1 and 2, respectively. The major findings were that (a) a 30-day washout period is insufficient time for muscle phosphocreatine to return to baseline following creatine supplementation but is sufficient time for plasma and urine creatine levels to return to presupplementation values; (b) postsupplementation muscle phosphocreatine levels were similar following bouts 1 and 2 despite 23% higher presupplementation muscle phosphocreatine before bout 2; and (c) the increased muscle phosphocreatine that persisted throughout the 30-day washout period corresponded with maintenance of increased body mass ( + 2.0 kg). Athletes should be aware that the washout period for muscle creatine to return to baseline levels may be longer than 30 days in some individuals, and this may be accompanied by a persistent increase in body mass. [ABSTRACT FROM AUTHOR]