Jessica Hill

Influence of tart cherry juice on indices of recovery following marathon running

This investigation determined the efficacy of a tart cherry juice in aiding recovery and reducing muscle damage, inflammation and oxidative stress. Twenty recreational Marathon runners assigned to either consumed cherry juice or placebo for 5 days before, the day of and for 48 h following a Marathon run. Markers of muscle damage (creatine kinase, lactate dehydrogenase, muscle soreness and isometric strength), inflammation [interleukin‐6 (IL‐6), C‐reactive protein (CRP) and uric acid], total antioxidant status (TAS) and oxidative stress [thiobarbituric acid reactive species (TBARS) and protein carbonyls] were examined before and following the race. Isometric strength recovered significantly faster (P=0.024) in the cherry juice group. No other damage indices were significantly different. Inflammation was reduced in the cherry juice group (IL‐6, P<0.001; CRP, P<0.01; uric acid, P<0.05). TAS was ∼10% greater in the cherry juice than the placebo group for all post‐supplementation measures (P<0.05). Protein carbonyls was not different; however, TBARS was lower in the cherry juice than the placebo at 48 h (P<0.05). The cherry juice appears to provide a viable means to aid recovery following strenuous exercise by increasing total antioxidative capacity, reducing inflammation, lipid peroxidation and so aiding in the recovery of muscle function.

Compression garments and recovery from exercise-induced muscle damage: a meta-analysis

The purpose of the study was to determine the effects of compression garments on recovery following damaging exercise. A systematic review and meta-analysis was conducted using studies that evaluated the efficacy of compression garments on measures of delayed onset muscle soreness (DOMS), muscular strength, muscular power and creatine kinase (CK). Studies were extracted from a literature search of online databases. Data were extracted from 12 studies, where variables were measured at baseline and at 24 or 48 or 72 h postexercise. Analysis of pooled data indicated that the use of compression garments had a moderate effect in reducing the severity of DOMS (Hedges’ g=0.403, 95% CI 0.236 to 0.569, p<0.001), muscle strength (Hedges’ g=0.462, 95% CI 0.221 to 0.703, p<0.001), muscle power (Hedges’ g=0.487, 95% CI 0.267 to 0.707, p<0.001) and CK (Hedges’ g=0.439, 95% CI 0.171 to 0.706, p<0.001). These results indicate that compression garments are effective in enhancing recovery from muscle damage.

Influence of compression garments on recovery after marathon running.

Abstract Hill, JA, Howatson, G, van Someren, KA, Walshe, I, and Pedlar, CR. Influence of compression garments on recovery after marathon running. J Strength Cond Res 28(8): 2228–2235, 2014—Strenuous physical activity can result in exercise-induced muscle damage. The purpose of this study was to investigate the efficacy of a lower limb compression garment in accelerating recovery from a marathon run. Twenty four subjects (female, n = 7; male, n = 17) completed a marathon run before being assigned to a treatment group or a sham treatment group. The treatment group wore lower limb compression tights for 72 hours after the marathon run, the sham treatment group received a single treatment of 15 minutes of sham ultrasound after the marathon run. Perceived muscle soreness, maximal voluntary isometric contraction (MVIC), and serum markers of creatine kinase (CK) and C-reactive protein (C-RP) were assessed before, immediately after, and 24, 48, and 72 hours after the marathon run. Perceived muscle soreness was significantly lower (p ⩽ 0.05) in the compression group at 24 hours after marathon when compared with the sham group. There were no significant group effects for MVIC, CK, and C-RP (p > 0.05). The use of a lower limb compression garment improved subjective perceptions of recovery; however, there was neither a significant improvement in muscular strength nor a significant attenuation in markers of exercise-induced muscle damage and inflammation.

Trekking Poles Reduce Exercise-Induced Muscle Injury during Mountain Walking

UNLABELLED Temporary muscle damage precipitated by downhill walking affects muscle function and potentially exposes muscle to further musculoskeletal injury. PURPOSE We hypothesized that the use of trekking poles would help maintain muscle function and reduce indices of muscle damage after a days mountain trekking. METHODS Thirty-seven physically active males (n = 26) and females (n = 11) volunteered to participate and were divided into either a trekking pole (TP) or no pole (NP) group. Participants carried a day sack (5.6 ± 1.5 kg) and made the ascent and descent of the highest peak in England and Wales (Mount Snowdon). HR and RPE were recorded during the ascent and descent. Indices of muscle damage, namely, maximal voluntary contraction, muscle soreness, creatine kinase (CK), and vertical jump performance, were measured before, immediately after (except CK), and 24, 48, and 72 h after trek. RESULTS HR was not different between groups, although RPE was significantly lower in TP during the ascent. The TP group showed attenuation of reductions in maximal voluntary contraction immediately after and 24 and 48 h after the trek; muscle soreness was significantly lower at 24 and 48 h after the trek, and CK was also lower at 24 h after the trek in the TP group. No differences in vertical jump were found. CONCLUSIONS Trekking poles reduce RPE on mountain ascents, reduce indices of muscle damage, assist in maintaining muscle function in the days after a mountain trek, and reduce the potential for subsequent injury.

Alterations in redox homeostasis in the elite endurance athlete.

BackgroundThe production of reactive oxygen (ROS) and nitrogen species (RNS) is a fundamental feature of mammalian physiology, cellular respiration and cell signalling, and essential for muscle function and training adaptation. Aerobic and anaerobic exercise results in alterations in redox homeostasis (ARH) in untrained, trained and well trained athletes. Low to moderate doses of ROS and RNS play a role in muscle adaptation to endurance training, but an overwhelming increase in RNS and ROS may lead to increased cell apoptosis and immunosuppression, fatigued states and underperformance.ObjectivesThe objectives of this systematic review are: (a) to test the hypotheses that ARH occur in elite endurance athletes; following an acute exercise bout, in an endurance race or competition; across a micro-, meso- or macro-training cycle; following a training taper; before, during and after altitude training; in females with amenorrhoea versus eumenorrhoea; and in non-functional over-reaching (NFOR) and overtraining states (OTS); (b) to report any relationship between ARH and training load and ARH and performance; and (c) to apply critical difference values for measures of oxidative stress/ARH to address whether there is any evidence of ARH being of physiological significance (not just statistical) and thus relevant to health and performance in the elite athlete.MethodsElectronic databases, Embase, MEDLINE, and SPORTDiscus were searched for relevant articles. Only studies that were observational articles of cross-sectional or longitudinal design, and included elite athletes competing at national or international level in endurance sports were included. Studies had to include biomarkers of ARH; oxidative damage, antioxidant enzymes, antioxidant capacity, and antioxidant vitamins and nutrients in urine, serum, plasma, whole blood, red blood cells (RBCs) and white blood cells (WBCs). A total of 3,057 articles were identified from the electronic searches. Twenty-eight articles met the inclusion criteria and were included in the review.ResultsARH occurs in elite endurance athletes, after acute exercise, a competition or race, across training phases, and with natural or simulated altitude. A reduction in ARH occurs across the season in elite athletes, with marked variation around intensified training phases, between individuals, and the greatest disturbances (of physiological significance) occurring with live-high-train-low techniques, and in athletes competing. A relationship with ARH and performance and illness exists in elite athletes. There was considerable heterogeneity across the studies for the biomarkers and assays used; the sport; the blood sampling time points; and the phase in the annual training cycle and thus baseline athlete fitness. In addition, there was a consistent lack of reporting of the analytical variability of the assays used to assess ARH.ConclusionsThe reported biochemical changes around ARH in elite athletes suggest that it may be of value to monitor biomarkers of ARH at rest, pre- and post-simulated performance tests, and before and after training micro- and meso-cycles, and altitude camps, to identify individual tolerance to training loads, potentially allowing the prevention of non-functionally over-reached states and optimisation of the individual training taper and training programme.

The effects of compression garment pressure on recovery from strenuous exercise

Compression garments are frequently used to facilitate recovery from strenuous exercise. PURPOSE To identify the effects of 2 different grades of compression garment on recovery indices after strenuous exercise. METHODS Forty-five recreationally active participants (n = 26 male and n = 19 female) completed an eccentric-exercise protocol consisting of 100 drop jumps, after which they were matched for body mass and randomly but equally assigned to a high-compression pressure (HI) group, a low-compression pressure (LOW) group, or a sham ultrasound group (SHAM). Participants in the HI and LOW groups wore the garments for 72 h postexercise; participants in the SHAM group received a single treatment of 10-min sham ultrasound. Measures of perceived muscle soreness, maximal voluntary contraction (MVC), countermovement-jump height (CMJ), creatine kinase (CK), C-reactive protein (CRP), and myoglobin (Mb) were assessed before the exercise protocol and again at 1, 24, 48, and 72 h postexercise. Data were analyzed using a repeated-measures ANOVA. RESULTS Recovery of MVC and CMJ was significantly improved with the HI compression garment (P < .05). A significant time-by-treatment interaction was also observed for jump height at 24 h postexercise (P < .05). No significant differences were observed for parameters of soreness and plasma CK, CRP, and Mb. CONCLUSIONS The pressures exerted by a compression garment affect recovery after exercise-induced muscle damage, with higher pressure improving recovery of muscle function.

Antioxidant supplementation does not attenuate exercise-induced cardiac troponin release

Clinically, cardiac troponins (cTn) are used as sensitive markers ofcardiomyocyte damage [1,2] with any elevation in cTn being related topoor prognosis [3]. Recently, however, exercise has also been shown tostimulate the release of cTn [4–6]. The mechanism responsible forexercise-induced cTn release is not known, and is currently a matter ofdebate [7]. Notwithstanding this, it has been proposed, due to therelatively low post-exercise cTn concentrations and its rapid clearance,that cTn is likely released from the cytosolic pool and not from thebreakdownofcontractileapparatus.Previousauthors[8]havesuggestedthatoxidativestressassociatedwithprolongedexercisemaydamagethecardiomyocyte membrane, resulting in cTn release from the cytosol.Antioxidant supplementation has been shown to attenuate oxidativestress, inflammation and muscle damage indices following strenuousexercise [9]; therefore, if post-exercise cTn release is related tocardiomyocyte membrane damage we hypothesised that antioxidantsupplementation would reduce cTn release following marathonrunning.The institutional ethics committee approved all procedures [11].Followinghealth-screeningandgainingconsent,16marathonrunners(11 male and 5 female), a subset from a previous study [9], free fromnutritional supplements and medication, volunteered to participate.Runners were assigned to either a placebo or antioxidant group in adouble-blind, randomised fashion. Antioxidant or placebo supple-mentation was administered each day from 5 days prior to 48 hfollowing the marathon. Indices of cardiac damage (cTnI), inflamma-tion (IL-6 and C-RP), muscle damage (CK), and total antioxidativecapacity (TAC) were taken before supplement (TAC only), before therace, immediately post, 24 and 48 h following completion of themarathon.The antioxidant supplement (tart cherry juice, Cherrypharm, Inc,Geneva, NY) has previously been shown to reduce skeletal muscledamage [10], reduce lipid peroxidation and aid recovery followingrunning [9]. Two servings (morning and afternoon) of approximately225 mL (equating to ~50–60 cherries) were consumed per day; thejuice contained ~600 mg of phenolic compounds such as anthocya-nins and other flavonoids (quercetin, kaempferol and isoramnetin)and ~55 mmol L

PRESSURES EXERTED BY COMMERCIALLY AVAILABLE LOWER LIMB COMPRESSION GARMENTS

Background Commercially available compression garments (CGs) enhance recovery from exercise in some, but not all studies. It has been suggested that the minimum physiologically effective pressure is 17.3 mmHg at the lower leg decreasing to 15.1 mmHg at the thigh (Watanuki and Murata, 1994). CGs are usually fitted using a generalised sizing system based on height and mass, potentially causing variability in the pressure exerted by the garment. Objective We aimed to quantify the pressure, and the variability in pressure, exerted on the leg by CGs fitted according to the manufacturers instructions. Participants 50 healthy, physically active individuals (n=26 male, n=24 female; age 18–65years) volunteered to participate. Design Participants were fitted with CGs according to manufacturers guidelines. The compressive force of the garments was measured in participants standing in the anatomical position including: the medial aspect of the calf at the site of maximal girth and at the midpoint of the femur measured between the inguinal crease and the superior aspect of the patella, of the lower limb. Data were compared to target pressure values. Results Pressure fell short of target values by 3% and 20% at the calf and by 34% and 47% at the thigh for males and females respectively. Figure 1 Box plots representing the mean, standard deviation, upper and lower quartiles for pressure exerted at the calf and thigh for males and females and compared to the target pressure suggested by Watanuki and Murata (1994). Conclusion Many individuals may not be experiencing an adequate pressure from CG (Figure 1); this might explain the inconsistency within the literature regarding CG and recovery. Future research should measure and control for actual pressure exerted by the garment.

Energy Drink Doses Of Caffeine And Taurine Have A Null Or Negative Effect On Sprint Performance

This study investigated the effects of caffeine and taurine co-ingestion on repeat-sprint cycling performance and associated physiological and perceptual responses. In a double blind, cross-over, repeated measures study, 11 male participants (age 21 ± 2 years; stature 178 ± 7 cm; body mass 80 ± 13 kg) completed 10 x 6-s sprints on a cycle ergometer, each separated by 24-s, an hour after ingesting: caffeine (80 mg) and taurine (1 g), equivalent to the amount observed in popular commercial energy drinks, or placebo (maltodextrin ∼1 g) in a gelatine capsule. Performance was measured on a cycle ergometer, whilst blood lactate concentration (B[la]), rating of perceived exertion (RPE) and heart rate (HR) were measured at baseline (pre-exercise) and after sprints 5 and 10. Magnitude-based inferences revealed likely, trivial differences in peak power and unclear, trivial inter-sprint fatigue index after ingestion of the caffeine and taurine supplement. Intra-sprint fatigue was greater in the caffeine and taurine condition at sprint 10 (likely, small) and possibly smaller in sprints 6-9. The caffeine and taurine supplement had a likely large effect on HR at baseline (ES = 0.94) and increases in B[la] after sprint 5 (likely small) and 10 (possibly small). There was no effect of the supplement on RPE (unclear, trivial). Administration of caffeine and taurine at doses equivalent to commercial energy drinks did not improve repeat-sprint cycling performance and appeared to induce greater fatigue within selected sprints, particularly at the end of the trial. This undesirable performance effect occurs in parallel with increased HR and glycolytic metabolic bi-products.

Efficacy of Compression Garments on Recovery From a Simulated Rugby Protocol

Abstract Upton, CM, Brown, FC, and Hill, JA. Efficacy of compression garments on recovery from a simulated rugby protocol. J Strength Cond Res 31(11): 2977–2982, 2017—The aim of this study was to examine the efficacy of lower limb compression garments on recovery in club-level rugby players. Nineteen participants (age, 20.3 ± 1.7 years, height, 184.2 ± 7.5 cm, and body mass, 89.5 ± 9.9 kg) completed a rugby-specific, muscle-damaging protocol before being assigned to a compression garment group (n = 10) or a SHAM (“recovery” drink) treatment (n = 9). The compression group wore the garments for 48 hours after exercise, whereas SHAM consumed a sweetened, low energy drink within an hour of protocol completion. Perceived muscle soreness (PMS), creatine kinase (CK), maximal voluntary isometric contraction (MVIC), and countermovement jump (CMJ) height were measured at baseline, post, 24, and 48 hours after exercise. Perceived muscle soreness was significantly lower in the compression group compared with the SHAM group at both 24 and 48 hours after exercise (p ⩽ 0.05). The compression group was also subject to lower CK values than SHAM, as demonstrated by a significant time by group effect (p ⩽ 0.05). There was no significant group effect for MVIC or CMJ (p > 0.05). Wearing compression garments after a rugby-specific, muscle-damaging protocol seems to reduce PMS and circulating concentrations of CK, suggesting improved recovery from muscle-damaging exercise.