Search results for "MPI"
showing 10 items of 3922 documents
Voluntary activation and mechanical performance of human triceps surae muscle after exhaustive stretch-shortening cycle jumping exercise.
2003
The purpose of this study was to examine neuromuscular factors that may contribute to post exercise force loss and subsequent recovery after exhaustive stretch-shortening cycle (SSC) exercise. Six subjects were fatigued on a sledge apparatus by 100 maximal rebound jumps followed by continuous submaximal jumping until complete exhaustion. Exercise-induced changes in neuromuscular performance were followed up to 7 days post exercise. The total number of jumps in the SSC exercise ranged from 336 to 1392. The SSC exercise induced a significant immediate plantarflexion torque decline of 29, 38 and 44% (P<0.05) in maximal voluntary contraction and evoked maximal twitch and low-frequency (LF) stim…
The effect of fatigue on store and re-use of elastic energy in slow and fast types of human skeletal muscle
1986
Stretch-shortening exercises are characterized by enhancement of performance when compared to the work output performed in shortening conditions. There is evidence that fast subjects are unable to re-use great amounts of elastic energy during stretch-shortening cycles performed with slow stretching speed and large stretching length. In the present study, 14 subjects possessing different fibre types in m. vastus lateralis performed vertical jumps with and without preliminary countermovement and with large angular displacement and slow stretching speed The jumping tests were executed before and immediately after fatigue induced by short intense exercises (60 s of continuous rebound jumping). …
Parent contributions to friendship stability during the primary school years.
2018
The present study examines whether characteristics of parents predict the stability of a child’s best friendships across the primary school years. Participants included 1,523 Finnish children (766 boys) who reported involvement in a total of 1,326 reciprocated friendship dyads in the 1st grade (M = 7.16 years old). At the onset of the study, mothers and fathers completed questionnaires describing their own parenting (i.e., behavioral control, psychological control, and affection toward the child) and depressive symptoms. Child scores for peer status (i.e., acceptance and rejection) were derived from 1st grade peer nomination data. Discrete-time survival analyses predicted the occurrence and…
Clinical impact of broad-spectrum empirical antibiotic therapy in patients with healthcare-associated pneumonia: a multicenter interventional study
2012
Healthcare-associated pneumonia (HCAP) has been proposed as a new category of pneumonia distinct from community-acquired pneumonia (CAP). A multicenter observational study in 2008 finds that patients with HCAP have a mortality rate significantly higher than patients with CAP, and a worse outcome is associated at logistic regression analysis with a low adherence to empirical antibiotic therapy recommended by ATS/IDSA guidelines. We designed a prospective interventional study to establish whether administration of a broad-spectrum antibiotic therapy consistent with the 2005 ATS/IDSA guidelines has an effect on the clinical outcome of hospitalized patients with HCAP. All patients with HCAP pro…
Effects of a 12-week strength training program on experimented fencers' movement time.
2014
The purpose of this study was to determine the effects of a 12-week strength training program on movement time (MT) on fencers of national level. Twelve male fencers were randomly divided into 2 groups: the control group (CG: N = 6; age, 22.3 ± 8.1 years) and the treatment group (TG: N = 6; age, 24.8 ± 7.2 years). The CG fencers followed the standard physical conditioning program, which was partially modified for the TG. The TG participated in a 12-week strength training program divided into 2 parts: maximal strength training, including weightlifting exercises (2 days a week for 6 weeks) and explosive strength training, with combined weights and plyometric exercises (2 days a week for 6 wee…
Neuromuscular and physiological variables evolve independently when running immediately after cycling
2015
International audience; During the early period of running after cycling, EMG patterns of the leg are modified in only some highly trained triathletes. The majority of studies have analysed muscle EMG patterns at arbitrary, predetermined time points. The purpose of this study was to examine changes to EMG patterns of the lower limb at physiologically determined times during the cycle-run transition period to better investigate neuromuscular adaptations. Six highly trained triathletes completed a 10 min isolated run (IR), 30 min of rest, then a 20 min cycling procedure, before a 10 min transition run (C-R). Surface EMG activity of eight lower limb muscles was recorded, normalised and quantif…
Does gender really matter? A structural equation model to explain risky and positive cycling behaviors
2018
Abstract Introduction While the use of bicycles as mean of transport is growing worldwide, the increasing rates of traffic crashes involving cyclists have turned into a relevant scientific, public health, and road safety concern. According to several studies, and despite the fact that some countries are taking part in preventive actions, the data indicate that the problem of cycling injuries implies high costs for the community welfare, for the economy, and for healthcare systems, thus proving a clear need for solutions. In this regard, and considering the available empirical evidence, risky and positive riding behaviors have gained significant weight in terms of explaining, intervening in,…
Treatment of human brucellosis with rifampin plus minocycline
2003
In order to evaluate the efficacy and tolerability of a high intravenous dose of rifampin plus oral minocycline (administered daily for 3 weeks) for the treatment of acute brucellosis, we retrospectively reviewed the outcome of 239 consecutive patients (135 adults and 104 children) diagnosed and treated over a 17-year period in Italy. The combination used resulted in 100% response and a relapse rate lower than 2%. Fifty-two (30 adults and 22 children) (29.8%) complained of mild adverse effects including an increase in aspartate aminotransferase (>250 IU) observed in 12 cases and considered related to rifampin and in 11 cases a reversible hyperpigmentation of the tongue attributed to minocyc…
Changes in neuromuscular performance and muscle fiber characteristics of elite power athletes self-administering androgenic and anabolic steroids
1984
The influence of androgenic-anabolic steroid-induced changes in measures of body composition, muscle fiber characteristics and various aspects of the neuromuscular performance of the leg extensor muscles was investigated in five experimental and six control power athletes during the 24-week programmed strength training followed by the additional six week training without hormone drugs. The mean values of the dosages of self-administration during the 24-week period were 31.0 +/- 14.3 mg/day for anabolic steroids (methandienone, stanozolol, nandrolone) and 178.4 +/- 82.7 mg/week for testosterone. During the 24-week hormone period the experimental group gained in fat-free weight (p less than 0…
The Effects of Electromyostimulation Training and Basketball Practice on Muscle Strength and Jumping Ability
2000
The aim of this study was to investigate the influence of a 4-week electromyostimulation training program on the strength of the knee extensors and the vertical jump performance of 10 basketball players. Electromyostimulation sessions were carried out 3 times weekly; each session consisted of 48 contractions. Testing was carried out before and after the electromyostimulation training program (week 4) and once more after 4 weeks of normal basketball training (week 8). At week 4, isokinetic strength increased significantly (p < 0.05) at eccentric and high concentric velocities (between 180 and 360 x s(-1)); this was not the case for low concentric velocities (60 and 120 degrees x s(-1)). Elec…