18 research outputs found
Effects of pomegranate supplementation on exercise performance and post-exercise recovery in healthy adults: A systematic review
© The Authors 2018. The functional significance of pomegranate (POM) supplementation on physiological responses during and following exercise is currently unclear. This systematic review aimed (i) to evaluate the existing literature assessing the effects of POM supplementation on exercise performance and recovery; exercise-induced muscle damage, oxidative stress, inflammation; and cardiovascular function in healthy adults and (ii) to outline the experimental conditions in which POM supplementation is more or less likely to benefit exercise performance and/or recovery. Multiple electronic databases were used to search for studies examining the effects of POM intake on physiological responses during and/or following exercise in healthy adult. Articles were included in the review if they investigated the effects of an acute or chronic POM supplementation on exercise performance, recovery and/or physiological responses during or following exercise. The existing evidence suggests that POM supplementation has the potential to confer antioxidant and anti-inflammatory effects during and following exercise, to improve cardiovascular responses during exercise, and to enhance endurance and strength performance and post-exercise recovery. However, the beneficial effects of POM supplementation appeared to be less likely when (i) unilateral eccentric exercise was employed, (ii) the POM administered was not rich in polyphenols (<1·69 g/l) and (iii) insufficient time was provided between POM-ingestion and the assessment of physiological responses/performance (≤1 h). The review indicates that POM has the potential to enhance exercise performance and to expedite recovery from intensive exercise. The findings and recommendations from this review may help to optimise POM-supplementation practice in athletes and coaches to potentially improve exercise-performance and post-exercise recovery
Independent and combined effects of all-out sprint and low-intensity continuous exercise on plasma oxidative stress biomarkers in trained judokas
The purpose of this study was to assess oxidative stress biomarkers prior to and following different forms of exercise. Ten elite
male judokas (age: 18.1±1.7 years, athletic experience: 6 years with a training frequency of 6 Judo-sessions/week) performed
three cycle ergometry sessions comprising a 30s Wingate test (MAX), 30 min at 60% maximal-aerobic-power-output (LOW) or these
two exercise protocols combined (COMBINED) in a repeated-measures design. Venous blood-samples were collected before, and
0(P0), 5(P5), 10(P10) and 20(P20) min after each exercise protocol and assessed for malondialdehyde concentration ([MDA]),
glutathione peroxidase (GPX), superoxide dismutase (SOD) and glutathione reductase (GR) content, and total-antioxidant-status
(TAS). Plasma [MDA] was found to be increased above baseline at P0 and P5 in the MAX, LOW and COMBINED conditions (p<0.05), but
was greater at P10 and P20 in the LOW condition compared to MAX and COMBINED conditions (p<0.05). Plasma GPX and SOD content
increased above baseline at P0 in MAX and COMBINED and at P5 in LOW (p<0.05), with GR content being similar between groups at
P0 and P5 (p>0.05). Twenty min post-exercise, plasma GPX, SOD, GR content and TAS were lower in the MAX compared to the LOW
and COMBINED conditions (p<0.05). In conclusion, the findings from this study reveal that redox-related biomarkers exhibited
divergent response dynamics following different forms of exercise, which might have implications for understanding the
mechanisms of exercise-induced skeletal muscle fatigue and adaptive remodeling
Effects of playing surface on physical, physiological and perceptual responses to a repeated sprint ability test: natural grass versus artificial turf
Purpose: The effect of playing surface on physical performance during a repeated sprint ability (RSA) test, and the mechanisms for any potential playing-surface-dependent effects on RSA performance, is equivocal. The purpose of this study was to investigate the effect of natural grass (NG) and artificial turf (AT) on physical performance, ratings of perceived exertion (RPE), feeling scale (FS) and blood biomarkers related to anaerobic contribution [lactate (Lac)], muscle damage [creatine kinase (CK) and lactate dehydrogenase (LDH)], inflammation [c-reactive protein (CRP)] and immune function [neutrophils (NEU), lymphocytes (LYM) and monocytes (MON)] in response to a RSA test. Methods: Nine male professional football players from the same regional team completed two sessions of RSA testing (6 × 30 s interspersed by 35 s recovery) on NG and AT in a randomized order. During the RSA test, total (sum of distances) and peak (highest distance covered in a single repetition) distance covered were determined using a measuring tape and the decrement in sprinting performance from the first to the last repetition was calculated. Before and after the RSA test, RPE, FS, and blood [Lac], [CK], [LDH], [CRP], [NEU], [LYM] and [MON] were recorded in both NG and AT conditions. Results: Although physical performance declined during the RSA blocks on both surfaces (p=0.001), the distance covered declined more on NG (15%) compared to AT [11%; p=0.04, ES=-0.34, 95% CI (-1.21, 0.56)] with a higher total distance covered (+6 ± 2%) on AT [p=0.018, ES=1.15, 95% CI (0.16, 2.04)]. In addition, lower RPE [p=0.04, ES=-0.49, 95% CI (-1.36, 0.42)] and blood [Lac], [NEU] and [LYM] [p=0.03; ES=-0.80, 95% CI (-1.67, 0.14); ES=-0.16, 95% CI (-1.03, 0.72) and ES=-0.94, 95% CI (-1.82, 0.02), respectively)] and more positive feelings [p=0.02, ES=0.81, 95%CI (-0.13, 1.69)] were observed following the RSA test performed on AT compared to NG. No differences were observed in the remaining physical and blood markers. Conclusion: These findings suggest that RSA performance is enhanced on AT compared to NG. This effect was accompanied by lower fatigue perception and blood [Lac], [NEU] and [LYM], and a more pleasurable feeling. These observations might have implications for physical performance in intermittent team sports athletes who train and compete on different playing surfaces
Effects of pomegranate juice supplementation on oxidative stress biomarkers following weightlifting exercise
The aim of this study was to test the hypothesis that pomegranate juice supplementation would blunt acute and delayed oxidative stress responses after a weightlifting training session. Nine elite weightlifters (21.0 ±1 years) performed two Olympic-Weightlifting sessions after ingesting either the placebo or pomegranate juice supplements. Venous blood samples were collected at rest and 3 min and 48 h after each session. Compared to the placebo condition, pomegranate juice supplementation
attenuated the increase in malondialdehyde (-12.5%; p < 0.01) and enhanced the enzymatic (+8.6% for catalase and +6.8% for glutathione peroxidase; p < 0.05) and non-enzymatic (+12.6% for uric acid and +5.7% for total bilirubin; p < 0.01) antioxidant responses shortly (3 min) after completion of the training session. Additionally, during the 48 h recovery period, pomegranate juice supplementation accelerated (p < 0.05) the recovery kinetics of the malondialdehyde (5.6%) and the enzymatic antioxidant defenses compared to the placebo condition (9 to 10%). In conclusion, supplementation with pomegranate juice has the potential to attenuate oxidative stress by enhancing antioxidant responses assessed acutely and up to 48 h following an intensive weightlifting training session. Therefore, elite weightlifters might benefit from blunted oxidative stress responses following intensive weightlifting sessions, which could have implications for recovery between training sessions
The impact of a 40‐min nap on neuromuscular fatigue profile and recovery following the 5‐m shuttle run test
Summary: This study aims to investigate the impact of a 40‐min nap opportunity on perceived recovery, exertion, and maximal voluntary isometric contraction (MVIC) following the 5‐m shuttle run test (5SRT), after 1 night of normal sleep. In a randomised, counterbalanced, cross‐over design, 17 trained men (mean [SD] age 20 [3] years, height 173 [6] cm, body mass 68 [6] kg) performed a 5SRT under two conditions: a 40‐min nap opportunity and no‐nap condition. After both conditions, electromyography signals during a 5‐s isometric knee extension were recorded before and immediately after the 5SRT. Two electrical nerve stimulations at the femoral nerve were measured during and after the MVIC. Force, voluntary activation level, M‐wave amplitudes, potentiated twitch, and electromyography signals (root mean square) were measured during each MVIC. Perceived exertion was recorded after each repetition of the test and perceived recovery was determined after the end of the MVIC. Compared to the no‐nap condition, the 40‐min nap resulted in significant enhancements in both the highest distance (p < 0.01, Δ = +7.6%) and total distance (p < 0.01, Δ = +7.5%). Before and after exercise, values for MVIC, root mean square, M‐wave amplitudes, and voluntary activation level were improved after the 40‐min nap opportunity compared to no‐nap condition (all p ≤ 0.01). Values for perceived exertion and recovery were improved after the 40‐min nap opportunity in comparison with no‐nap condition (p ≤ 0.01). A 40‐min nap opportunity improved repeated high‐intensity short‐term maximal performance, perceived recovery, associated neuromuscular responses, and reduced perceived fatigue. Therefore, our findings suggest that central and peripheral processes are involved in the improvements of 5SRT performance after napping.</p
The effects of Ramadan intermittent fasting on sleep-wake behaviour and daytime sleepiness in team sport referees
The aim of the present study was to evaluate the impact of Ramadan fasting on sleep quality and daytime sleepiness in team sport referees. Seventy-eight male amateur team sport referees (age: 31.1 ± 10.8 years) participated in this study. Participants responded to the Arabic version of the Pittsburgh Sleep Quality Index (PSQI) and the Epworth sleepiness scale (ESS) questionnaires before (10-days prior) and during (last 7-days) the month of Ramadan. PSQI and ESS scores increased significantly during Ramadan (both p < .001, ES = 0.56 and 0.54, respectively) with 83.3% of participants scoring ≥5 in the PSQI. The percentage of participants suffering from severe excessive daytime sleepiness (ESS score ≥ 16) was 3.8% before vs. 7.7% during Ramadan (p < 0.001). Sleep duration decreased by ~ 1 h during Ramadan (p < .001, ES = 0.61) and was associated with a delay in bedtime of ~ 2 h (p < 0.001, ES = 0.7) and of wake-up time of ~ 1 h (p < 0.001, ES = 0.5). The score for daytime dysfunction and subjective sleep perception, as components of the PSQI, increased (both p < 0.001; ES = 0.79, ES = 0.57, respectively), whereas the score for the use of sleep medication decreased during vs. before Ramadan (p = 0.041, ES = 0.47). Ramadan fasting impaired sleep quality and increased daytime sleepiness in team sport referees. Future studies, using objective assessment tools, are warranted
Effects of natural polyphenol-rich pomegranate juice supplementation on plasma ion and lipid profiles following resistance exercise: a placebo-controlled trial
Background: Pomegranate juice (POMj) contains abundant soluble polyphenolic antioxidant compounds and is recommended for its cardioprotective/atheroprotective properties. However, very few studies have investigated the efficacy of POMj supplementation to alter physiological responses during intensive physical exercise. This placebo-controlled study aimed to examine whether supplementation with natural polyphenol-rich-POMj could influence the ionic or lipid responses to an intensive resistance training session in elite athletes. Methods: Nine elite weightlifters (21 ± 1 years) performed two Olympic-weightlifting sessions after ingesting placebo and POMj supplements. Venous blood samples were collected at rest and 3 min after each session for assessment of plasma sodium ([Na+]), potassium ([K+]), chloride ([Cl-]), calcium ([Ca2+]), triglyceride ([TG]) and high-density lipoprotein ([HDL-C]), low-density lipoprotein ([HDL-C]) and total ([TC]) cholesterol concentrations. Results: Plasma [K+] and [TG] were lowered post-exercise compared to resting values in the PLA condition (p = 0.03 for K+ and p = 0.02 for TG) with no pre-to-post exercise differences in the other plasma ion and lipid markers (p > 0.05). Compared to rest, plasma [Na+] and [Cl-] were increased (p = 0.04, %change = 4.10% for Na+ and p = 0.02, %change = 4.44% for Cl-), but there were no differences in the other plasma ion or lipid markers post-exercise after POMj supplementation (p > 0.05). Post-exercise plasma [Na+], [Cl-], and [HDL-C] were greater following POMj supplementation compared to PLA (p = 0.01 for Cl-A nd HDL-C, p = 0.02 for Na+, and p = 0.04 for TC), with no between-supplement post-exercise differences in the other ion and lipid markers (p > 0.05). Conclusion: In conclusion, supplementation with POMj has the potential to attenuate the acute imbalance of plasma [K+] and to improve blood lipid responses (i.e., HDL-C) following resistance exercises in elite weightlifters. However, further large research in both athletic and non-athletic populations is needed to corroborate these preliminary observations and to elucidate the potential underlying mechanisms and translational potential of our novel observations. Trial registration: Name of the registry: ClinicalTrials.gov PRS The registration number: NCT02697903. Date of Registry: 03/03/2016 'Retrospectively registered'. The registration title: Pomegranate Improve Biological Recovery Kinetics in Elite Weightlifter. Graphical abstract: [Figure not available: See fulltext.
Experimental design.
<p><i>NB</i>: the pre sessions 1 and 2 values correspond to values of 48-h recovery; Weightlifting performance was calculated during both test sessions; Acute (RPE) and delayed (DOMS) perceived muscle fatigue and soreness were assessed respectively 3min and 48 after both test sessions.</p
RPE values using Placebo and natural POMj supplementations.
<p>*: Significant differences between PLA and POMj conditions.</p
Acute biological responses to weightlifting training sessions using natural POMj and PLA supplementations.
<p>Acute biological responses to weightlifting training sessions using natural POMj and PLA supplementations.</p