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External Counterpulsation (ECP) is a well-established treatment for coronary disease, with interest growing in the potential to act as a sports recovery modality or pre-performance strategy. This pilot study compared the effects of different ECP durations upon neuromuscular function (NF), cortisol and subjective perceptions in a rested state. Eleven physically active male volunteers received two ECP treatments (Renew Sport, Singapore) of differing duration (20-min and 40-min) in a randomised, repeated measures crossover design. Testing occurred pre-ECP, post-ECP, and 24-h post-ECP. NF testing comprised counter-movement jumps (CMJs) and 6-s sprint cycling. Saliva samples were analysed for cortisol. Rate of Perceived Exertion (RPE, 6 to 20) and Bipolar Comfort Scales (− 10 to 10) quantified participants’ experiences, and ECP duration preference was examined. Repeated measures ANOVA and effect size (ES: Cohen’s d) analysed NF and cortisol results. Paired t-tests analysed RPE and comfort ratings. ECP demonstrated no effect, neither positive nor negative, upon NF outcome measures in both groups. A trend of reduced salivary cortisol levels across both groups following ECP was observed (P = 0.066). No RPE difference existed between groups. 20-min of ECP was rated as significantly more comfortable than 40-min (P

To examine the effect of acute quercetin (Q) ingestion on neuromuscular function, biomarkers of muscle damage, and rate of perceived exertion (RPE) in response to an acute bout of resistance training. 10 young men (22.1 ± 1.8 years, 24.1 ± 3.1 BMI) participated in a randomized, double-blind, crossover study. Subjects consumed Q (1 g/day) or placebo (PLA) 3 h prior to a resistance training session which consisted of 3 sets of 8 repetitions at 80% of the one repetition maximum (1RM) completed bilaterally for eight different resistance exercises. Electromyographic (EMG) signals were recorded from the knee extensor muscles during maximal isometric (MVIC) and isokinetic voluntary contractions, and during an isometric fatiguing test. Mechanical and EMG signals, biomarkers of cell damage, and RPE score were measured PRE, immediately POST, and 24 h (blood indices only) following the resistance exercise. After a single dose of Q, the torque–velocity curve of knee extensors was enhanced and after the resistance exercise, subjects showed a lower MVIC reduction (Q: 0.91 ± 6.10%, PLA: 8.66 ± 5.08%) with a greater rate of torque development (+ 10.6%, p

Age-related reductions in strength and power are considered to negatively impact balance control, but the existence of a direct association is still an issue of debate. This is possibly due to the fact that balance assessment is complex, reflects different underlying physiologic mechanisms and involves quantitative measurements of postural sway or timing of performance during balance tasks. The present study evaluated the moderator effect of static postural control on the association of power and strength with dynamic balance tasks. Fifty-seven healthy 65–75 year old individuals performed tests of dynamic functional balance (walking speed under different conditions) and of strength, power and static postural control. Dynamic balance performance (walking speed) was associated with lower limb strength and power, as well as postural control under conditions requiring postural adjustments (narrow surface walking r 2 = 0.31, p

Stiffness, the relationship between applied load and elastic deformation, is an important neuromechanical component related to muscular performance and injury risk. The free-oscillation technique is a popular method for stiffness assessment. There has been wide application of this technique assessing a variety of musculature, including the triceps surae, knee flexors, knee extensors and pectorals. The methodology involves the modelling of the system as a linear damped mass-spring system. The use of such a model has certain advantages and limitations that will be discussed within this review. Perhaps the major advantage of such a model is the specificity of the measure, whereby it is possible for the assessment conditions to simulate the type of loading witnessed during functional tasks and sporting situations. High levels of reliability and construct validity have typically been reported using such procedures. Despite these assurances of accuracy, a number of issues have also been identified. The literature reveals some concerns surrounding the use of a linear model for stiffness assessment. Further, procedural issues surrounding the administration of the perturbation, attention focus of the participant during the perturbation, signal collection, data processing and analysis, presentation of stiffness as a linear or torsional value, assessment load (single vs multiple vs maximal) and the stiffness-load relationship have been identified, and are all fundamentally related to the quality of the calculated output data. Finally, several important considerations for practitioners have been recommended to ensure the quality and consistency of stiffness data collection, processing and interpretation. © 2011 Adis Data Information BV. All rights reserved.