In the original version of this article, the legends to Figs. 2, 3 and 4 were inadvertently swapped. This has now been corrected in the PDF and HTML versions of the article.
(1) Introduction: Soccer players face high demand for training and games. To facilitate their performance, many studies have investigated ergogenic supplements that can assist in the recovery and ...performance of players. The aim of this research was to assess whether caffeine supplementation can help soccer players’ recovery and performance. (2) Methods: Professional players were given 210 mg of caffeine or placebo in seven games during the state championship, being offered placebo in three matches and caffeine in four matches, administered 30 min before the game, during the game, and after the game. Blood creatine kinase (CK) and heart rate variability (HRV) were measured. Participants rated their perceived recuperation (RPR) and exertion (RPE) on scales developed by Laurent and Borg, respectively. The time that the player spent on the field was also evaluated. t-tests and Levene’s test were used to analyze the results. In addition to mean differences, variations in the results were also analyzed. (3) Results: No significant differences were found in CK, HRV, RPR, RPE, or minutes on the field when comparing caffeine supplementation with the placebo. (4) Conclusion: Caffeine supplementation throughout the championship appears to have had no ergogenic effect on athlete performance and recovery.
Space flight diets include a 55/30/15 (carbohydrate/fat/protein) ratio. Yet recent long-term missions require astronauts to exercise several hours daily for up to seven days a week. We hypothesize a ...high protein diet (45/25/30) is more conducive to longer missions and their high volumes of exercise.
With a within-subjects design, participants (8 men, 8 women) adhered to each diet for 14 days. Isocaloric diets were prescribed based on subject’s resting metabolic rate, activity level and body composition. Compliance was monitored daily. Per subject, diet sequence was randomized to limit order effects. Immediately after each diet concluded subjects worked out on a gravity-independent device (Impulse Training Systems; Newnan, GA) while tethered to a metabolic cart. Workouts entailed four (unilateral knee extension, unilateral hip extension, unilateral standing row, bilateral arm pulldown) exercises, comprised of three 60-second sets separated by 60-second rests and done against 4.4 kg. Work volumes were measured from our device, as were pre-exercise respiratory quotients (RQ), and energy costs based on net O2 uptakes. Blood lactate concentrations (BLa-) were measured before and five minutes after workouts. Exercise and respiratory data were compared with 2(gender) × 2(diet) ANOVAs, with repeated measures for diet. BLa- were assessed with a 2(gender) × 2(time) × 2(diet) ANOVA, with repeated measures for time and diet.
Significant BLa- differences occurred for time (post > pre) and for RQ by diet (55/30/15 > 45/25/30). Trends for work differences occurred by gender (men > women) and diet (45/25/30 > 55/30/15).
Our preliminary results concur with those that show greater RQ values from diets higher in carbohydrates. With continued data collection it is of interest to note if inter-work differences reach statistical significance, with higher values produced by the high protein diet. If so, such a diet may be more efficacious as a countermeasure to the muscle atrophy, strength loss and performance decrements for in-flight operational tasks seen with longer missions.
Kentucky Space Grant Consortium.
Youth in weight-classified combat sports may attempt to change body weight to gain performance advantage. Differences between weight-for-age percentiles (WAP) and performance in youth wrestlers ...remains unknown. The purpose of this retrospective study was to examine the differences in performance between wrestlers above and below the 50th WAP over a wrestling season.
Participants included 22 male wrestlers from a team in the Pennsylvania Elementary Wrestling League (8.8 ± 2.1 years of age, 2.3 ± 2.3 years of experience). Retrospective data included age, weight, years of experience, family history, and frequency of wins, losses and forfeits over a 3-month wrestling season. Average WAP were calculated using CDC growth charts and wrestlers were assigned to one of two groups <50 th WAP (n = 10) and >50 th WAP (n = 12). Wrestlers were also categorized into two groups in terms of experience (≤2 years, >2 years). Differences between the two groups in performance variables were examined using ANOVA.
We observed a significant difference between <50th and >50th WAP groups in total forfeits (0.6 ± 1.0; 2.0 ± 1.5, respectively, P < 0.02). There was an interaction observed between WAP group and years of experience in number of total forfeits (P < 0.132) such that wrestlers with <2 years of experience and <50th WAP experienced fewer total forfeits (0.3 ± 0.8) than those >50th percentile (2.0 ± 1.4). Those with more experience in <50th WAP also had fewer forfeits compared to >50th WAP. A similar interaction was observed between WAP group and years of experience in number of total losses (P < 0.187). Wrestlers with <2 years of experience, and <50th WAP experienced more total losses (4.8 ± 1.5) than wrestlers >50th WAP (2.0 ± 1.4). Those with more experience and <50th WAP experienced fewer losses than those >50th WAP.
We observed a significant difference in forfeits between average WAP groups and an interaction between experience and WAP groups in losses and forfeits in this small sample. Further research is needed to provide insight into how WAP mayaffect performance in this population. Future research may include a larger population, and variables such as BMI-for-age, hydration status, nutrition, body composition and additional factors that affect both weight and performance.
n/a.
The objective of this experiment was to determine the branched-chain amino acid (BCAA) content in five different sport nutrition supplements compared to the amount claimed on the label.
To measure ...the BCAA content of five nutritional supplements, a leucine dehydrogenase enzyme assay was used. This enzyme catalyzes the reaction of turning the given BCAA (L-leucine, L-valine, and L-isoleucine), water, and NAD+ into their respective metabolite, NH3, NADH, and H+. Ultraviolet-visible light spectrophotometry (UV/Vis) was used at 340 nm to create a standard curve. This curve uses the Beer-Lambert Law to measure NADH concentration from absorbance. NADH is in a 1:1 ratio with each BCAA molecule thus relaying the content of the given sample. The assay is specific to the three BCAAs in their free form. Other amino acids, as well as BCAAs in oligopeptides, do not interfere with this experiment. Products including oligo- and polypeptides were not included for testing. The assay was performed for each product and ran against a known standard (≥98% L-leucine) for validation. Due to different supplements having different BCAA amounts per serving, % content of the claimed amount was measured.
Compared to the amount provided by the labels of each supplement, BCAA content was on average only 61% of the manufacturer claims when compared to ≥98% L-leucine. This shows that these BCAA supplements do not meet label claims for BCAA content (P < 0.01).
The five tested nutritional supplements contain significantly less branched-chain amino acid content than claimed on the label. This experiment can be expanded on in the future to test content of other BCAA containing supplements to determine how common underdosing is in the industry as a whole.
The author claims no funding sources.
Energy drinks have been anecdotally associated with deleterious cardiovascular health outcomes. These drinks contain ingredients which could affect glycemic response to the carbohydrate content. The ...aim of this study was to determine if acute exercise would alter the glycemic and physiological response to the consumption of Monster Energy.
Following an overnight fast, human subjects (19.1 ± 1.4 years; 30 female; 5 male) were randomized to exercise on a stationary bike at 33% of their predicted VO2 max for 10 minutes with a five minute sitting rest after, or sitting (control) for 15 minutes prior to ingestion of Monster Energy. Blood glucose, heart rate, and blood pressure were measured 0-, 30-, 60-, and 90-minutes postprandially. Data is represented as LSM ± SE with significance analyzed using a t-test, or multiple comparison test (P < 0.05).
Blood glucose (mg/dL) for control at 0-, 30-, 60-, and 90-minutes 91.5 ± 1.2, 133.7 ± 4.3, 96.3 ± 4.2, and 82.4 ± 1.8 mg/dL, respectively. For those receiving bike exercise prior to ingestion blood glucose was 92.2 ± 1.2, 126.6 ± 3.8, 92.5 ± 2.3, 84.0 ± 1.8 mg/dL. Within group significance in both groups was observed between 0 and 30, 30 and 60, and 60 and 90, for control only, there were no significant blood glucose differences observed between groups across time. Heart rate for control at 0-, 30-, 60-, and 90-minutes was 78.0 ± 3.1, 78.2 ± 2.5, 78.6 ± 2.6, and 74.4 ± 1.9 respectively. For those receiving bike exercise prior to ingestion heart rate was 88.7 ± 3.71, 85.5 ± 2.7, 83.1 ± 2.3, and 80.3 ± 2.9, with significance between 0 and 90 minutes. Mean arterial blood pressure for control at 0-, 30-, 60-, and 90-minutes was 86.8 ± 2.6, 89.2 ± 2.1, 89.2 ± 2.5, and 87.6 ± 2.6. For those receiving bike exercise prior to ingestion blood pressure was 90.6 ± 3.1, 88.98 ± 2.3, 88.2 ± 2.0, and 87.0 ± 2.9 with no significant differences.
Exercise probably does not alter the glycemic and physiological response to energy drinks.
WSU Biology Department.
This study was designed to evaluate the efficacy of an herbal blend composed of Sphaeranthus indicus and Mangifera indica extracts to improve muscle health.
In a randomized, double-blind, ...placebo-controlled study, 40 male participants of 18–40 yrs age, were assigned to receive 650 mg of LI12542F6 (A) or Placebo (P) for 56 days. The primary endpoint was change from baseline in muscle strength, assessed by 1-RM Bench and Leg presses. Secondary endpoints included muscle endurance, time to exhaustion, muscle size, body composition and free testosterone. Safety was also assessed.
Significant (P < 0.0001) increases in change from baseline for strength (bench and leg presses and grip strength) were observed in the A vs. P group beginning at 14 d and continuing throughout the study. Muscle endurance and time to exhaustion were similarly increased by 14 d and continued for the remainder of the study. By day 56, the mid upper arm circumference was statistically increased in A vs. P (P < 0.05) in left and right arms.
Significant improvements in muscle endurance and strength were observed in resistance trained healthy men consuming LI12542F6 daily for 56 days. Further research will elucidate efficacy in other populations.
Laila Nutraceuticals.
Disordered eating (DE), although subclinical, increases the risk for clinical eating disorders and is prevalent in collegiate athletes. At the same time, athletes are often more aware of and ...therefore behave in ways that modify their body composition, as it can influence performance. Despite this understanding, relevant data is lacking and therefore research is needed to establish prevalence rates within specific collegiate sports, and to better understand the relationships between DE behaviors and body composition in student athletes. Therefore, the aims of this study were 1) to determine the prevalence of DE among collegiate athletes and 2) to determine the relationship between prevalence of DE behaviors and body composition.
NCAA Division 1 student athletes (n = 56) during the 2018–2019 academic year were recruited from various sports: football (n = 13), men’s soccer (n = 2), women’s soccer, (n = 13), women’s swimming (n = 12), women’s basketball (n = 12), track and field (n = 4), and gymnastics (n = 8). DE was assessed using the Eating Attitudes Test (EAT-26) questionnaire, which classified athletes as either asymptomatic (EAT-26 < 20) or symptomatic (EAT-26 > 20). Height and weight were measured and % body fat, fat mass and lean mass were assessed by dual energy X-ray absorptiometry.
Athlete ages ranged between 18–22 years, 71% (n = 40) identified as female, and their mean BMI was 25.4 kg/m2. No athletes met criteria to be classified as symptomatic for DE (EAT-26 range: 0 to 15). Female athletes had higher mean EAT-26 scores than males (5.6 ± 3.8 vs 2.9 ± 2.1, P = 0.008). Gymnastics had the highest mean EAT-26 score (7.3 ± 3.9) and football had the lowest (3.4 ± 3.5). Although there were no correlations between EAT-26 and % body fat (P = 0.345) or fat mass (P = 0.984), it was negatively correlated with lean mass (P = 0.038).
In contrast to current research, no athletes were at risk for disordered eating. Despite this, the fact that asymptomatic EAT-26 scores (which assesses prevalence of DE behavior) were still inversely correlated with lean mass, prompts a need for further research to clarify these interactions in collegiate athletes.
N/A.
Carbohydrate (CHO) ingestion is an established nutritional strategy to improve endurance performance, yet currently available products may contribute to gastrointestinal (GI) distress. Potatoes have ...a high-glycemic index, indicating that their CHO content is readily available. We aimed to compare the effects of ingesting potato purée (POT), commercial CHO gel (GEL), or a control (water, CTL) during cycling on GI Symptoms and affective indices in trained athletes.
In a randomized crossover study, twelve trained cyclists (9 M and 3F; 30.5 ± 8.7y; 70.6 ± 7.6 kg; 1.70 ± 7 cm; 60.7 ± 8.9 mL/kg/min) completed a 2 h cycling challenge (60–85%VO2max) followed by a 6 kJ/kg time trial. Cyclists were randomly assigned to consume POT, GEL, or CTL during the challenge. Rating of perceived exertion (RPE), GI symptoms, and affective responses (Feeling Scale −5/+5) were collected throughout the challenge via visual analog scales. Differences between treatments were assessed by mixed model analysis of variance using time and condition as a fixed factor and subject as a random factor. All data represent mean ± standard deviation.
RPE was not different between POT, GEL, or CTL condition at the end of the cycling challenge (POT: 17 ± 1; GEL: 17 ± 1, CTL: 18 ± 1, P > 0.05). Higher GI symptoms (P < 0.01) were observed at the end of the challenge during POT condition (15 ± 3%) when compared to GEL (8 ± 3%) and CTL (7 ± 3%), with no significant difference in these symptoms prior to this time. FS response significantly increased (P = 0.04) during POT trial (2 ± 2) compared to GEL (0 ± 0.2) and CTL (0 ± 2) conditions at end of the challenge.
While POT ingestion resulted in greater GI distressed compared to CHO gel, cyclists perceived the exertion to be similar and even reported feeling more pleasant after POT ingestion in endurance exercise.
Alliance for Potato Research and Education.
New Zealand blackcurrant (NZBC) is an anthocyanin-rich berry with potential effects on cardiovascular health (e.g., 7-day NZBC extract lowered total peripheral resistance at rest). We examined ...effects of 7- and 14-day intake of NZBC extract on cardiovascular responses during moderate intensity exercise.
Fifteen healthy men (mean ± SD, age: 24 ± 6 yr, body mass: 79 ± 16 kg, height: 178 ± 6 cm, BMI: 24.7 ± 4.3 kg·m−2, IPAQ score: 4534 ± 1576 MET·week−1) volunteered. Resting metabolic equivalent (1-MET) was measured using Douglas bags (1-MET: 3.97 ± 0.66 ml·kg−1·min−1) with an incremental walking test to determine the relationship between walking speed and MET. A randomised, cross-over experimental design was used for baseline, 7-day and 14-day intake. Participants consumed 2 capsules of NZBC extract (600 mg and containing 210 mg of anthocyanins, CurraNZ™ Health Currancy Ltd., UK) with breakfast with a 14-day washout. On the morning of testing, the final 2 capsules were ingested 2-hr before the 30-min walk at 4 (n = 3) or 5 (n = 12) METs (speed: 5.68 ± 0.67 km·hr−1). Cardiovascular responses were measured at 7–10, 17–20 and 27–30 min during the walk (Portapres Model 2), averaged and analysed (ANOVA and post-hoc t-tests).
Intake duration had no effect on heart rate (e.g., baseline: 102 ± 18 beats·min−1), systolic blood pressure (e.g., baseline 158 ± 18 mm Hg) and ejection time (e.g., baseline: 0.28 ± 0.03 s). Cardiac output (baseline: 11.7 ± 2.0, 7-day: 12.7 ± 2.5, 14-day: 12.7 ± 2.1 L·min−1, P = 0.012) and stroke volume (baseline: 114 ± 13, 7-day: 123 ± 22, 14-day: 126 ± 21 mL·min−1, P = 0.017) were increased, and total peripheral resistance (baseline: 0.51 ± 0.11, 7-day: 0.46 ± 0.17, 14-day: 0.44 ± 0.12 mmHg·L−1·min−1, P = 0.018) and diastolic blood pressure (baseline 71 ± 9, 7-day: 66 ± 10, 14-day: 63 ± 11 mm Hg, P = 0.002) were lower for 7- and 14-day intake. Only 14-day intake resulted in lower mean arterial pressure (baseline: 93 ± 10, 7-day: 89 ± 9, 14-day: 87 ± 11 mm Hg, P = 0.034).
Beneficial effects of anthocyanin-rich NZBC extract intake on cardiovascular responses during moderate intensity exercise do not require long-duration intake.
Health Currancy (UK) Ltd and CurraNZ (NZ) Ltd provided supplements and support for conference attendance with Blackcurrant New Zealand Inc. (NZ).
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