The Effects of Pre-conditioning on Exercise-Induced Muscle Damage: A Systematic Review and Meta-analysis

Background: Several studies have utilised isometric, eccentric and downhill walking pre-conditioning as a strategy for alleviating the signs and symptoms of exercise-induced muscle damage (EIMD) following a bout of damaging physical activity. Objectives: This systematic review and meta-analysis examined the effects of pre-conditioning strategies on indices of muscle damage and physical performance measures following a second bout of strenuous physical activity. Data Sources: PubMed, CINAHL and Scopus. Eligibility Criteria: Studies meeting the PICO (population, intervention/exposure, comparison, and outcome) criteria were included in this review: (1) general population or “untrained” participants with no contraindications affecting physical performance; (2) studies with a parallel design to examine the prevention and severity of muscle-damaging contractions; (3) outcome measures were compared using baseline and post-intervention measures; and (4) outcome measures included any markers of indirect muscle damage and muscular contractility measures. Participants: Individuals with no resistance training experiences in the previous 6 or more months. Interventions: A single bout of pre-conditioning exercises consisting of eccentric or isometric contractions performed a minimum of 24 h prior to a bout of damaging physical activity were compared to control interventions that did not perform pre-conditioning prior to damaging physical activity. Study Appraisal: Kmet appraisal system. Synthesis Methods: Quantitative analysis was conducted using forest plots to examine standardised mean differences (SMD, i.e. effect size), test statistics for statistical significance (i.e. Z-values) and between-study heterogeneity by inspecting I2. Results: Following abstract and full-text screening, 23 articles were included in this paper. Based on the meta-analysis, the pre-conditioning group exhibited lower levels of creatine kinase at 24 h (SMD = − 1.64; Z = 8.39; p = 0.00001), 48 h (SMD = − 2.65; Z = 7.78; p = 0.00001), 72 h (SMD = − 2.39; Z = 5.71; p = 0.00001) and 96 h post-exercise (SMD = − 3.52; Z = 7.39; p = 0.00001) than the control group. Delayed-onset muscle soreness was also lower for the pre-conditioning group at 24 h (SMD = − 1.89; Z = 6.17; p = 0.00001), 48 h (SMD = − 2.50; Z = 7.99; p = 0.00001), 72 h (SMD = − 2.73; Z = 7.86; p = 0.00001) and 96 h post-exercise (SMD = − 3.30; Z = 8.47; p = 0.00001). Maximal voluntary contraction force was maintained and returned to normal sooner in the pre-conditioning group than in the control group, 24 h (SMD = 1.46; Z = 5.49; p = 0.00001), 48 h (SMD = 1.59; Z = 6.04; p = 0.00001), 72 h (SMD = 2.02; Z = 6.09; p = 0.00001) and 96 h post-exercise (SMD = 2.16; Z = 5.69; p = 0.00001). Range of motion was better maintained by the pre-conditioning group compared with the control group at 24 h (SMD = 1.48; Z = 4.30; p = 0.00001), 48 h (SMD = 2.20; Z = 5.64; p = 0.00001), 72 h (SMD = 2.66; Z = 5.42; p = 0.00001) and 96 h post-exercise (SMD = 2.5; Z = 5.46; p = 0.00001). Based on qualitative analyses, pre-conditioning activities were more effective when performed at 2–4 days before the muscle-damaging protocol compared with immediately prior to the muscle-damaging protocol, or 1–3 weeks prior to the muscle-damaging protocol. Furthermore, pre-conditioning activities performed using eccentric contractions over isometric contractions, with higher volumes, greater intensity and more lengthened muscle contractions provided greater protection from EIMD. Limitations: Several outcome measures showed high inter-study heterogeneity. The inability to account for differences in durations between pre-conditioning and the second bout of damaging physical activity was also limiting. Conclusions: Pre-conditioning significantly reduced the severity of creatine kinase release, delayed-onset muscle soreness, loss of maximal voluntary contraction force and the range of motion decrease. Pre-conditioning may prevent severe EIMD and accelerate recovery of muscle force generation capacity

Beyond shareholder primacy? Reflections on the trajectory of UK corporate governance.

Core institutions of UK corporate governance, in particular the City Code on Takeovers and Mergers, the Combined Code on Corporate Governance and the law on directors’ duties, are strongly orientated towards the norm of shareholder primacy. Beyond the core, however, stakeholder interests are better represented, in particular at the intersection of insolvency and employment law. This reflects the influence of European Community laws on information and consultation of employees. In addition, there are signs that some institutional shareholders are redirecting their investment strategies, under government encouragement, away from a focus on short-term returns, in such a way as to favour stakeholder-inclusive practices by firms. On this basis we suggest that the UK system is currently in a state of flux and that the debate over shareholder primacy has not been concluded

Inflammation and immunity in schizophrenia: implications for pathophysiology and treatment.

Complex interactions between the immune system and the brain might have important aetiological and therapeutic implications for neuropsychiatric brain disorders. A possible association between schizophrenia and the immune system was postulated over a century ago, and is supported by epidemiological and genetic studies pointing to links with infection and inflammation. Contrary to the traditional view that the brain is an immunologically privileged site shielded behind the blood-brain barrier, studies in the past 20 years have noted complex interactions between the immune system, systemic inflammation, and the brain, which can lead to changes in mood, cognition, and behaviour. In this Review, we describe some of the important areas of research regarding innate and adaptive immune response in schizophrenia and related psychotic disorders that, we think, will be of interest to psychiatric clinicians and researchers. We discuss potential mechanisms and therapeutic implications of these findings, including studies of anti-inflammatory drugs in schizophrenia, describe areas for development, and offer testable hypotheses for future investigations.The work was supported by a doctoral clinical research training fellowship grant from the Wellcome Trust to Golam Khandaker (094790/Z/10/Z; 2010-‘13), grants from the Stanley Medical Research Institute and the National Institutes of Mental Health (grant# MH-94268) to Robert Yolken, and grants from the Wellcome Trust (095844/Z/11/Z & 088869/Z/09/Z), and the NIHR (RP-PG-0606-1335) to Peter Jones.This is the accepted manuscript. The final version is available from Elsevier at http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366%2814%2900122-9/abstrac

Equal pay as a moving target: International perspectives on forty-years of addressing the gender pay gap

This paper provides an overview of the key factors impacting upon the gender pay gap in the UK, Europe and Australia. Forty years after the implementation of the first equal pay legislation, the pay gap remains a key aspect of the inequalities women face in the labour market. While the overall pay gap has tended to fall in many countries over the past forty years, it has not closed; in some countries it has been stubbornly resistant, or has even widened. In reviewing the collection of papers that make up this special issue we identify four broad themes with which to group the contributions and draw out the explanations for diverse trends: theoretical and conceptual debates; legal developments and their impacts; wage setting institutions and changing employer demands; and newly emerging pay inequalities between and within educational and ethnic groups. Across the four themes we underline how the trends in the gender pay gap capture the dynamism of inequalities, as the market power of different groups and stakeholders changes over times. Three key dimensions emerge from the papers to provide a framework for future research and policy discourse: the relationship between litigation and bargaining strategies; the interaction between wage-setting institutions and new organisational practices; and the increasing and range of diversity or equality strands competing for equal treatment. We conclude that progress towards closing the gender pay gap will not be easy, will require a collective effort of various actors, and will not be quick

Oxytocin increases eye contact during a real-time, naturalistic social interaction in males with and without autism.

Autism spectrum conditions (autism) affect ~1% of the population and are characterized by deficits in social communication. Oxytocin has been widely reported to affect social-communicative function and its neural underpinnings. Here we report the first evidence that intranasal oxytocin administration improves a core problem that individuals with autism have in using eye contact appropriately in real-world social settings. A randomized double-blind, placebo-controlled, within-subjects design is used to examine how intranasal administration of 24 IU of oxytocin affects gaze behavior for 32 adult males with autism and 34 controls in a real-time interaction with a researcher. This interactive paradigm bypasses many of the limitations encountered with conventional static or computer-based stimuli. Eye movements are recorded using eye tracking, providing an objective measurement of looking patterns. The measure is shown to be sensitive to the reduced eye contact commonly reported in autism, with the autism group spending less time looking to the eye region of the face than controls. Oxytocin administration selectively enhanced gaze to the eyes in both the autism and control groups (transformed mean eye-fixation difference per second=0.082; 95% CI:0.025-0.14, P=0.006). Within the autism group, oxytocin has the most effect on fixation duration in individuals with impaired levels of eye contact at baseline (Cohen's d=0.86). These findings demonstrate that the potential benefits of oxytocin in autism extend to a real-time interaction, providing evidence of a therapeutic effect in a key aspect of social communication.We are grateful to the Autism Research Trust (ART) for funding the consumable costs of this study. BA was supported by the Wellcome Trust. SBC and BC were supported by the MRC during the period of this work. This study was conducted in association with the NIHR CLAHRC-EoE, and the EU-AIMS IMI. MVL was supported by a postdoctoral fellowship from the British Academy. MH was supported by the Deutsche Forschungsgemeinschaft (DFG, HE 5310/1-1) and the European Neuroscience Network NEUREX.This is the final published version. It first appeared at http://www.nature.com/tp/journal/v5/n2/full/tp2014146a.html