A narrative review on the potential of red beetroot as an adjuvant strategy to counter fatigue in children with cancer

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Cancer-related fatigue (CRF) is a debilitating adverse effect among children with cancer and a significant barrier to physical activity (PA) participation. PA interventions are effective at reducing fatigue and improving both quality of life (QOL) and functional outcomes in children with cancer. However, 50–70% of children with cancer do not meet PA guidelines. Thus, adjuvant methods are needed to increase PA participation. Given the growing interest in the use of beetroot juice to reduce exercise-induced fatigue, our narrative review evaluated the potential use of beetroot to improve PA participation to counter CRF and improve QOL. Our review of 249 articles showed a lack of published clinical trials of beetroot in children and adults with cancer. Trials of beetroot use had been conducted in a noncancer population (n = 198), and anticancer studies were primarily in the preclinical phase (n = 40). Although results are promising, with beetroot juice shown to counter exercise-induced fatigue in a variety of athletic and patient populations, its use to counter CRF in children with cancer is inconclusive. Pilot and feasibility studies are needed to examine the potential benefits of beetroot to counter CRF, increase PA participation, and improve QOL in children with cancer

The plasma bioavailability of nitrate and betanin from Beta vulgaris rubra in humans

Purpose: To evaluate the plasma bioavailability of betanin and nitric oxide (NOx) after consuming beetroot juice (BTJ) and whole beetroot (BF). BTJ and BF were also analysed for antioxidant capacity, polyphenol content (TPC) and betalain content. Methods: Ten healthy males consumed either 250 ml of BTJ, 300 g of BF or a placebo drink, in a randomised, crossover design. Venous plasma samples were collected pre (baseline), 1, 2, 3, 5 and 8 h post-ingestion. Betanin content in BTJ, BF and plasma was analysed with reverse-phase high-performance liquid chromatography (HPLC) and mass spectrometry detection (LCMS). Antioxidant capacity was estimated using the Trolox equivalent antioxidant capacity (TEAC) and polyphenol content using Folin–Ciocalteu colorimetric methods [gallic acid equivalents (GAE)] and betalain content spectrophotometrically. Results: TEAC was 11.4 ± 0.2 mmol/L for BTJ and 3.4 ± 0.4 μmol/g for BF. Both BTJ and BF contained a number of polyphenols (1606.9 ± 151 mg/GAE/L and 1.67 ± 0.1 mg/GAE/g, respectively), betacyanins (68.2 ± 0.4 mg/betanin equivalents/L and 19.6 ± 0.6 mg/betanin equivalents/100 g, respectively) and betaxanthins (41.7 ± 0.7 mg/indicaxanthin equivalents/L and 7.5 ± 0.2 mg/indicaxanthin equivalents/100 g, respectively). Despite high betanin contents in both BTJ (~194 mg) and BF (~66 mg), betanin could not be detected in the plasma at any time point post-ingestion. Plasma NOx was elevated above baseline for 8 h after consuming BTJ and 5 h after BF (P < 0.05). Conclusions: These data reveal that BTJ and BF are rich in phytonutrients and may provide a useful means of increasing plasma NOx bioavailability. However, betanin, the major betalain in beetroot, showed poor bioavailability in plasma

The plasma bioavailability of nitrate and betanin from Beta vulgaris rubra in humans

Purpose: To evaluate the plasma bioavailability of betanin and nitric oxide (NOx) after consuming beetroot juice (BTJ) and whole beetroot (BF). BTJ and BF were also analysed for antioxidant capacity, polyphenol content (TPC) and betalain content. Methods: Ten healthy males consumed either 250 ml of BTJ, 300 g of BF or a placebo drink, in a randomised, crossover design. Venous plasma samples were collected pre (baseline), 1, 2, 3, 5 and 8 h post-ingestion. Betanin content in BTJ, BF and plasma was analysed with reverse-phase high-performance liquid chromatography (HPLC) and mass spectrometry detection (LCMS). Antioxidant capacity was estimated using the Trolox equivalent antioxidant capacity (TEAC) and polyphenol content using Folin–Ciocalteu colorimetric methods [gallic acid equivalents (GAE)] and betalain content spectrophotometrically. Results: TEAC was 11.4 ± 0.2 mmol/L for BTJ and 3.4 ± 0.4 μmol/g for BF. Both BTJ and BF contained a number of polyphenols (1606.9 ± 151 mg/GAE/L and 1.67 ± 0.1 mg/GAE/g, respectively), betacyanins (68.2 ± 0.4 mg/betanin equivalents/L and 19.6 ± 0.6 mg/betanin equivalents/100 g, respectively) and betaxanthins (41.7 ± 0.7 mg/indicaxanthin equivalents/L and 7.5 ± 0.2 mg/indicaxanthin equivalents/100 g, respectively). Despite high betanin contents in both BTJ (~194 mg) and BF (~66 mg), betanin could not be detected in the plasma at any time point post-ingestion. Plasma NOx was elevated above baseline for 8 h after consuming BTJ and 5 h after BF (P < 0.05). Conclusions: These data reveal that BTJ and BF are rich in phytonutrients and may provide a useful means of increasing plasma NOx bioavailability. However, betanin, the major betalain in beetroot, showed poor bioavailability in plasma

The effects of collagen peptides on muscle damage, inflammation and bone turnover following exercise: a randomized, controlled trial

This study examined whether consuming collagen peptides (CP) before and after strenuous exercise alters markers of muscle damage, inflammation and bone turnover. Using a double-blind, independent group's design, 24 recreationally active males consumed either 20 g day-1 of CP or a placebo control (CON) for 7 days before and 2 days after performing 150 drop jumps. Maximal isometric voluntary contractions, countermovement jumps (CMJ), muscle soreness (200 mm visual analogue scale), pressure pain threshold, Brief Assessment of Mood Adapted (BAM +) and a range of blood markers associated with muscle damage, inflammation and bone turnover C-terminal telopeptide of type 1 collagen (β-CTX) and N-terminal propeptides of type 1 pro-collagen (P1NP) were measured before supplementation (baseline; BL), pre, post, 1.5, 24 and 48 h post-exercise. Muscle soreness was not significantly different in CP and CON (P = 0.071) but a large effect size was evident at 48 h post-exercise, indicative of lower soreness in the CP group (90.42 ± 45.33 mm vs. CON 125.67 ± 36.50 mm; ES = 2.64). CMJ height recovered quicker with CP than CON at 48 h (P = 0.050; CP 89.96 ± 12.85 vs. CON 78.67 ± 14.41% of baseline values; ES = 0.55). There were no statistically significant effects for the other dependent variables (P > 0.05). β-CTX and P1NP were unaffected by CP supplementation (P > 0.05). In conclusion, CP had moderate benefits for the recovery of CMJ and muscle soreness but had no influence on inflammation and bone collagen synthesis

The prevalence of disordered eating in elite male and female soccer players

PurposeTo examine the prevalence of disordered eating (DE) in elite male and female soccer players and the influence of perfectionism.MethodsUsing a cross-sectional design, elite male (n = 137) and female (n = 70) soccer players and non-athlete controls (n = 179) completed the clinical perfectionism questionnaire (CPQ-12) and the eating attitudes test (EAT-26) to assess perfectionism and DE risk, respectively.ResultsMale soccer players had higher EAT-26 scores than controls (10.4 ± 9.9 vs. 6.8 ± 6.7; P = 0.001), but there were no differences in the prevalence of clinical levels of DE (EAT-26 score ≥ 20) (15 vs. 5%, respectively; X2 = 0.079) The proportion of females with DE risk was higher in controls [EAT-26: 13.9 ± 11.6 (25% of population)] than female players [EAT-26: 10.0 ± 9.0% (11% of population)] (X2 = 0.001). With linear regression, perfectionism explained 20% of the variation in DE risk in males (P = 0.001); in females, athletic status (player vs. control) and perfectionism were significant predictors of DE risk, explaining 21% of the variation (P = 0.001). Male reserve team players had higher EAT-26 (+ 3.5) and perfectionism (+ 2.7) scores than first-team players (P ConclusionsThe prevalence of DE risk was not different in elite male and female soccer players; in fact, the prevalence was greatest in non-athlete female controls. Perfectionism is a significant predictor of DE risk in males and females.Level of evidenceIII, case–control study.</div

The effect of creatine supplementation on markers of exercise-induced muscle damage: A systematic review and meta-analysis of human intervention trials

This systematic review and meta-analysis examined the effects of creatine supplementation on recovery from exercise-induced muscle damage, and is reported according to the PRISMA guidelines. MEDLINE and SPORTDiscus were searched for articles from inception until April 2020. Inclusion criteria were adult participants (≥18 years); creatine provided before and/or after exercise versus a noncreatine comparator; measurement of muscle function recovery, muscle soreness, inflammation, myocellular protein efflux, oxidative stress; range of motion; randomized controlled trials in humans. Thirteen studies (totaling 278 participants; 235 males and 43 females; age range 20–60 years) were deemed eligible for analysis. Data extraction was performed independently by both authors. The Cochrane Collaboration Risk of Bias Tool was used to critically appraise the studies; forest plots were generated with random-effects model and standardized mean differences. Creatine supplementation did not alter muscle strength, muscle soreness, range of motion, or inflammation at each of the five follow-up times after exercise ( .05). Creatine attenuated creatine kinase activity at 48-hr postexercise (standardized mean difference: −1.06; 95% confidence interval [−1.97, −0.14]; p = .02) but at no other time points. High (I2; >75%) and significant (Chi2; p < .01) heterogeneity was identified for all outcome measures at various follow-up times. In conclusion, creatine supplementation does not accelerate recovery following exercise-induced muscle damage; however, well-controlled studies with higher sample sizes are warranted to verify these conclusions. Systematic review registration (PROSPERO CRD42020178735)

Professional academy soccer players’ perceived experiences of loan environments

The current investigation examined professional academy soccer players' perceived experiences of loan environments, compared to their previous academy experiences. Fifteen professional soccer players completed season-long loans at various European soccer clubs. Individual semi-structured interviews were conducted following the loans to determine the physical, technical, tactical, psychological, and psychosocial differences between their loan, and existing academy environments. Inductive content analysis was conducted on the interviews to build a system of categories explaining the holistic experiences of player’s loan experiences. Key themes that emerged were greater perceived physical demands on loan, but similar or lower technical demands. Players were exposed to a wider range of playing styles on loan. Some players struggled with the reduced feedback and communication surrounding their performances on loan compared to the academy, and had difficulty interacting with peers. The current investigation highlights areas for consideration to ensure a smooth transition between academy and loan environments

The influence of muscle strength and aerobic fitness on functional recovery in professional soccer

BACKGROUND: Well-developed physical qualities may protect athletes from exercise-induced muscle damage and accelerate recovery following exercise. This study examined the influence of muscle strength and aerobic fitness on recovery from competitive soccer matches.METHODS: Fourteen players from the English Premier League 2 (Age, 18 ± 1 yrs; height, 1.78 ± 0.54 m; mass, 73.8 ± 6.3 kg) were equally divided (median split) into a higher or lower group for muscle strength and aerobic fitness, according to their isometric mid-thigh pull (IMPT) and maximal aerobic speed test (MAST) scores, respectively. The following markers of recovery were assessed before (48-h pre-match), 12 h (M+1), 36 h (M+2) and 60 h (M+3) after ~3 matches: countermovement jump height (CMJ), reactive strength index (RSI), muscle soreness (DOMS) and wellbeing.RESULTS: IMTP was positively correlated with the recovery of CMJ, RSI and DOMS following matches (P0.05).CONCLUSIONS: This study showed that stronger players recovered quicker after matches and highlights the importance of lowerbody strength training for soccer players.</div

The influence of different sources of polyphenols on sub-maximal cycling and time trial performance

The primary purpose of the study was to establish the effects of commercially available polyphenol-rich antioxidant supplements, Pycnogenol® with added bioflavonoids (PYC-B) and CherryActive (CHA), on 20 km cycling performance. Using a double-blind counterbalanced, repeated-measures design, nine male cyclists or triathletes (32.1 ± 11.2 years; maximal aerobic capacity 4.2 ± 0.7 L•min-1; maximal power output 391.7 ± 39.5 watts) consumed 200 mg of CHA, 120 mg of PYC-B, or 200 mg of placebo (PLA) capsules, 2 days before and on the day of each experimental trial. The experimental trials consisted of four 5 minute stages at 40%, 50%, 60%, and 70% maximal power output (Wmax), followed by a 20 km time trial (TT). Statistical analysis revealed no significant differences between trials for heart rate, respiratory exchange ratio, gross mechanical efficiency, oxygen consumption, or blood lactate, at any of the intensities completed during the initial 20 minute phase of the trial (p>0.05). Final 20 km TT times were not significantly different between trials (p=0.115), but, compared to PLA, PYC-B did significantly increase power output by 6.2% over the final 5 km of the TT (p=0.022). The study suggests that the PYC-B supplement could be beneficial towards the end of an intense bout of cycling exercise. However, as total 20 km time was not significantly different between trials the doses used are unlikely to benefit 20 km cycling time trial performance

Effect of playing status and fixture congestion on training load, mental fatigue, and recovery status in Premier League academy goalkeepers

Soccer goalkeepers are a unique playing position and require specific programming. Despite this, there is a paucity of information surrounding their support. The current investigation quantified internal and external training loads on and recovery status of starting and substitute academy goalkeepers during 1 and 2 match-weeks. Six professional soccer goalkeepers played the role of starting and substitute goalkeepers during both 1 and 2 match-weeks, providing data for 4 within-subject conditions (START-1, SUB-1, START-2, and SUB-2). Internal and external training load data were collected using ratings of perceived exertion and global positioning systems for all matches and training sessions. Physical and perceived recovery status was also collected daily for all individuals. Training load and recovery variables were analyzed across 4 playing conditions and 4 time points using a repeated measures analysis of variance. Results demonstrated significant differences in internal and external weekly training loads and physical and perceived recovery measures between starting and nonstarting goalkeepers. In the training leading up to matches, SUB-1 and SUB-2 had higher internal and external training loads compared with START-1. On a match-day, SUB-1 and SUB-2 performed more high-intensity actions but covered less total and high-speed distance than START-1. Following matches, substitutes had higher volumes of external training loads compared with START-1. The higher training loads experienced by substitutes at various time points resulted in lower physical recovery status on a match-day and post-match. START-1 demonstrated higher mental fatigue and lower well-being compared with substitute goalkeepers after match. The current investigation offers valuable insights for the preparation of professional goalkeepers.</p