Introduction:In this study, we questioned whether local cooling of muscle or heating involving core and muscle temperatures are the main indicators for force variability.Methods:Ten volunteers performed a 2‐min maximum voluntary contraction (MVC) of the knee extensors under control (CON) conditions after passive heating (HT) and cooling (CL) of the lower body.Results:HT increased muscle and rectal temperatures, whereas CL lowered muscle temperature but did not affect rectal temperature. During 2‐min MVC, peak force decreased to a lower level in HT compared with CON and CL experiments. Greater central fatigue was found in the HT experiment, and there was less in the CL experiment than in the CON experiment.Conclusions:Increased core and muscle temperature increased physiological tremor and the amount and structural complexity of force variability of the exercising muscles, whereas local muscle cooling decreased all force variability variables measured. Muscle Nerve, 2012

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Rationale and ObjectivesPro-inflammatory processes have been argued to play a role in conditions associated with cognitive decline and neurodegeneration, like aging and obesity. Only a limited number of studies have tried to measure both peripheral and central biomarkers of inflammation and examined their interrelationship. The primary aim of this study was to examine the hypothesis that chronic peripheral inflammation would be associated with neurometabolic changes that indicate neuroinflammation (the combined elevation of myoinositol and choline), brain gray matter volume decrease, and lower cognitive functioning in older adults.Materials and MethodsSeventy-four older adults underwent bio-impedance body composition analysis, cognitive testing with the Montreal Cognitive Assessment (MoCA), blood serum analysis of inflammatory markers interleukin-6 (IL-6) and kynurenine, magnetic resonance imaging (MRI), and proton magnetic resonance spectroscopy (1H-MRS) of the brain. Neurometabolic findings from both Tarquin and LCModel 1H-MRS post-processing software packages were compared. The regions of interest for MRI and 1H-MRS measurements were dorsal posterior cingulate cortex (DPCC), left hippocampal cortex (HPC), left medial temporal cortex (MTC), left primary sensorimotor cortex (SM1), and right dorsolateral prefrontal cortex (DLPFC).ResultsElevated serum kynurenine levels were associated with signs of neuroinflammation, specifically in the DPCC, left SM1 and right DLPFC, and signs of neurodegeneration, specifically in the left HPC, left MTC and left SM1, after adjusting for age, sex and fat percentage (fat%). Elevated serum IL-6 levels were associated with increased Glx levels in left HPC, left MTC, and right DLPFC, after processing the 1H-MRS data with Tarquin. Overall, the agreement between Tarquin and LCModel results was moderate-to-strong for tNAA, tCho, mIns, and tCr, but weak to very weak for Glx. Peripheral inflammatory markers (IL-6 and kynurenine) were not associated with older age, higher fat%, decreased brain gray matter volume loss or decreased cognitive functioning within a cohort of older adults.ConclusionOur results suggest that serum kynurenine may be used as a peripheral inflammatory marker that is associated with neuroinflammation and neurodegeneration, although not linked to cognition. Future studies should consider longitudinal analysis to assess the causal inferences between chronic peripheral and neuroinflammation, brain structural and neurometabolic changes, and cognitive decline in aging.

Research background and hypothesis. Europeans have won Olympic and world gold medals since modern indoor men’s handball became an international sport (1938) and an Olympic sport (1972) (www. ihf.com). Nevertheless, no research has been carried out in order to find out the tendencies in European modern men’s handball. Research aim of this study was to illustrate discriminant indicators of sport performance between winners and losers in European men’s modern handball match activities. Research methods. Data sets were gathered from the European Handball Federation (EHF) website (http://www.eurohandball.com) covering the five European Men’s Handball Championships (EMHC): 2002, 2004, 2006, 2008 and 2010 (n = 239 matches). Each match was classified as successful and non-successful for each team, and then the number of analysed matches doubled to 478. We examined 28 variables of sport performance, but only 15 key indicators where significant discriminant between winners and losers at least in one EMHC was shown. Research results. Winners scored more goals (p < 0.01, p < 0.001), were better in total attack (p < 0.001) and positional attack (p < 0.01, p < 0.001), performed more efficiently in shooting total (p  < 0.001) and shooting from long distance (p < 0.01, p < 0.05), and goalkeepers saved more throws (p < 0.05, p < 0.001).Discussion and conclusions. Winning and losing teams played in the same pattern (p > 0.05). In many cases the separate match-play was determined by using temporal model of playing style. The phenomenon is that teams scored more goals in the second half than in the first one despite the fact that players’ activities decreased in the second half. Sport performance profile in European modern handball can generate a useful database.

The purpose of this investigation was to estimate the test-retest cross-reliability of peripheral and central changes with respect to nonlinear and linear measures of a surface electromyography (EMG) signal measured during isometric maximal voluntary contraction (MVC) combined with superimposed electrical stimulation during a brief and fatiguing task involving the ankle plantar flexors over 2 follicular phases of menstrual cycle. Ten healthy female adults underwent 1 familiarization session and 5 identical test-retest sessions. The results showed that the decrease in plantar flexor EMG components (root mean square [RMS], mean frequency [MnF], wavelet packet entropy [WPE]) for soleus and gastrocnemius muscles, central activation ratio (CAR) and MVC, and contractile properties (P20, P100, PTT-100, and half-relaxation time) of the plantar flexor muscles at the end of 2-minute MVC were similar (time effect; p < 0.001, η(p)² > 0.7, statistical power [SP] > 99%) and exhibited high stability over 5 trials (trial effect; p > 0.05; η(p)² < 0.2, SP < 30%). High reliability between trials was found for 5-second MVC (intraclass correlation coefficient [ICC] > 0.82, p < 0.001) and meaningful reliability for 2-minute MVC (ICC > 0.66, p < 0.01). In conclusion, in young healthy women, measurements of neuromuscular function, such as RMS, MnF, and WPE of a surface EMG signal, MVC, and CAR from a brief and sustained MVC of the ankle plantar flexors, are reliable, and multidimensional stability was found with respect to both high and low correlation outcomes across the 5 identical test-retest trials of any 2 properties measured during brief and sustained MVC.