Assessing the usefulness of acute physiological responses following resistance exercise: sensitivity, magnitude of change, and time course of measures.

A variety of strategies exist to modulate the acute physiological responses following resistance exercise aimed at enhancing recovery and/or adaptation processes. To assess the true impact of these strategies, it is important to know the ability of different measures to detect meaningful change. We investigated the sensitivity of measures used to quantify acute physiological responses to resistance exercise and constructed a physiological profile to characterise the magnitude of change and the time course of these responses. Eight males accustomed to regular resistance exercise performed experimental sessions during a "control week", void of an exercise stimulus. The following week, termed the "exercise week", participants repeated this sequence of experimental sessions, and they also performed a bout of lower-limb resistance exercise following the baseline assessments. Assessments were conducted at baseline and at 2, 6, 24, 48, 72, and 96 h after the intervention. On the basis of the signal-to-noise ratio, the most sensitive measures were maximal voluntary isometric contraction, 20-m sprint, countermovement jump peak force, rate of force development (100-200 ms), muscle soreness, Daily Analysis Of Life Demands For Athletes part B, limb girth, matrix metalloproteinase-9, interleukin-6, creatine kinase, and high-sensitivity C-reactive protein with ratios >1.5. Clear changes in these measures following resistance exercise were determined via magnitude-based inferences. These findings highlight measures that can detect real changes in acute physiological responses following resistance exercise in trained individuals. Researchers investigating strategies to manipulate acute physiological responses for recovery and/or adaptation can use these measures, as well as the recommended sampling points, to be confident that their interventions are making a worthwhile impact.

The Effects of Montmorency Tart Cherry Concentrate Supplementation on Recovery Following Prolonged, Intermittent Exercise.

This study investigated Montmorency tart cherry concentrate (MC) supplementation on markers of recovery following prolonged, intermittent sprint activity. Sixteen semi-professional, male soccer players, who had dietary restrictions imposed for the duration of the study, were divided into two equal groups and consumed either MC or placebo (PLA) supplementation for eight consecutive days (30 mL twice per day). On day 5, participants completed an adapted version of the Loughborough Intermittent Shuttle Test (LISTADAPT). Maximal voluntary isometric contraction (MVIC), 20 m Sprint, counter movement jump (CMJ), agility and muscle soreness (DOMS) were assessed at baseline, and 24, 48 and 72 h post-exercise. Measures of inflammation (IL-1-ß, IL-6, IL-8, TNF-α, hsCRP), muscle damage (CK) and oxidative stress (LOOH) were analysed at baseline and 1, 3, 5, 24, 48 and 72 h post-exercise. Performance indices (MVIC, CMJ and agility) recovered faster and muscle soreness (DOMS) ratings were lower in the MC group (p < 0.05). Additionally, the acute inflammatory response (IL-6) was attenuated in the MC group. There were no effects for LOOH and CK. These findings suggest MC is efficacious in accelerating recovery following prolonged, repeat sprint activity, such as soccer and rugby, and lends further evidence that polyphenol-rich foods like MC are effective in accelerating recovery following various types of strenuous exercise.

Phytochemical uptake following human consumption of Montmorency tart cherry (L. Prunus cerasus) and influence of phenolic acids on vascular smooth muscle cells in vitro.

PURPOSE: To investigate the phytochemical uptake following human consumption of Montmorency tart cherry (L. Prunus cerasus) and influence of selected phenolic acids on vascular smooth muscle cells in vitro. METHODS: In a randomised, double-blinded, crossover design, 12 healthy males consumed either 30 or 60 mL of Montmorency tart cherry concentrate. Following analysis of the juice composition, venous blood samples were taken before and 1, 2, 3, 5 and 8 h post-consumption of the beverage. In addition to examining some aspects of the concentrate contents, plasma concentrations of protocatechuic acid (PCA), vanillic acid (VA) and chlorogenic (CHL) acid were analysed by reversed-phase high-performance liquid chromatography (HPLC) with diode array for quantitation and mass spectrometry detection (LCMS) for qualitative purposes. Vascular smooth muscle cell migration and proliferation were also assessed in vitro. RESULTS: Both the 30 and 60 mL doses of Montmorency cherry concentrate contained high amounts of total phenolics (71.37 ± 0.11; 142.73 ± 0.22 mg/L) and total anthocyanins (62.47 ± 0.31; 31.24 ± 0.16 mg/L), as well as large quantities of CHL (0.205 ± 0.24; 0.410 ± 0.48 mg/L) and VA (0.253 ± 0.84; 0.506 ± 1.68 mg/L). HPLC/LCMS identified two dihydroxybenzoic acids (PCA and VA) in plasma following MC concentrate consumption. Both compounds were most abundant 1-2 h post-initial ingestion with traces detectable at 8 h post-ingestion. Cell migration was significantly influenced by the combination of PCA and VA, but not in isolation. There was no effect of the compounds on cell proliferation. CONCLUSIONS: These data show new information that phenolic compounds thought to exert vasoactive properties are bioavailable in vivo following MC consumption and subsequently can influence cell behaviour. These data may be useful for the design and interpretation of intervention studies investigating the health effects of Montmorency cherries.

Recovery facilitation with Montmorency cherries following high-intensity, metabolically challenging exercise.

The impact of Montmorency tart cherry (Prunus cerasus L.) concentrate (MC) on physiological indices and functional performance was examined following a bout of high-intensity stochastic cycling. Trained cyclists (n = 16) were equally divided into 2 groups (MC or isoenergetic placebo (PLA)) and consumed 30 mL of supplement, twice per day for 8 consecutive days. On the fifth day of supplementation, participants completed a 109-min cycling trial designed to replicate road race demands. Functional performance (maximum voluntary isometric contraction (MVIC), cycling efficiency, 6-s peak cycling power) and delayed onset muscle soreness were assessed at baseline, 24, 48, and 72 h post-trial. Blood samples collected at baseline, immediately pre- and post-trial, and at 1, 3, 5, 24, 48, and 72 h post-trial were analysed for indices of inflammation (interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor alpha, high-sensitivity C-reactive protein (hsCRP)), oxidative stress (lipid hydroperoxides), and muscle damage (creatine kinase). MVIC (P < 0.05) did not decline in the MC group (vs. PLA) across the 72-h post-trial period and economy (P < 0.05) was improved in the MC group at 24 h. IL-6 (P < 0.001) and hsCRP (P < 0.05) responses to the trial were attenuated with MC (vs. PLA). No other blood markers were significantly different between MC and PLA groups. The results of the study suggest that Montmorency cherry concentrate can be an efficacious functional food for accelerating recovery and reducing exercise-induced inflammation following strenuous cycling exercise.

Effects of seated and standing cold water immersion on recovery from repeated sprinting.

This study investigated the effects of two different hydrostatic pressures (seated or standing) during cold water immersion at attenuating the deleterious effects of strenuous exercise on indices of damage and recovery. Twenty four male well-trained games players (age 23 ± 3 years; body mass 81.4 ± 8.7 kg: [Formula: see text]O2max 57.5 ± 4.9 ml∙kg(-1)∙min(-1)) completed the Loughborough Intermittent Shuttle Test (LIST) and were randomly assigned to either a control, seated cold water immersion or a standing cold water immersion (14 min at 14°C). Maximal isometric voluntary contraction, counter-movement jump, creatine kinase, C-reactive protein, interleukin-6 and delayed onset muscle soreness (DOMS) were measured before and up to 72 h following the LIST. All dependent variables showed main effects for time (P < 0.05) following the LIST, indicating physiological stress and muscle damage following the exercise. There were no significant group differences between control and either of the cold water immersion interventions. Seated cold water immersion was associated with lower DOMS than standing cold water immersion (effect size = 1.86; P = 0.001). These data suggest that increasing hydrostatic pressure by standing in cold water does not provide an additional recovery benefit over seated cold water immersion, and that both seated and standing immersions have no benefit in promoting recovery following intermittent sprint exercise.

Montmorency cherries reduce the oxidative stress and inflammatory responses to repeated days high-intensity stochastic cycling.

This investigation examined the impact of Montmorency tart cherry concentrate (MC) on physiological indices of oxidative stress, inflammation and muscle damage across 3 days simulated road cycle racing. Trained cyclists (n = 16) were divided into equal groups and consumed 30 mL of MC or placebo (PLA), twice per day for seven consecutive days. A simulated, high-intensity, stochastic road cycling trial, lasting 109 min, was completed on days 5, 6 and 7. Oxidative stress and inflammation were measured from blood samples collected at baseline and immediately pre- and post-trial on days 5, 6 and 7. Analyses for lipid hydroperoxides (LOOH), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interleukin-8 (IL-8), interleukin-1-beta (IL-1-ß), high-sensitivity C-reactive protein (hsCRP) and creatine kinase (CK) were conducted. LOOH (p < 0.01), IL-6 (p < 0.05) and hsCRP (p < 0.05) responses to trials were lower in the MC group versus PLA. No group or interaction effects were found for the other markers. The attenuated oxidative and inflammatory responses suggest MC may be efficacious in combating post-exercise oxidative and inflammatory cascades that can contribute to cellular disruption. Additionally, we demonstrate direct application for MC in repeated days cycling and conceivably other sporting scenario's where back-to-back performances are required.