BACKGROUND The prevalence of self-reported upper respiratory tract (URT) symptoms in athletes has been traditionally associated with opportunistic infection during the temporal suppression of immune function after prolonged exercise. There is little evidence for this, and a competing noninfectious hypothesis has been proposed, whereby the exercise-induced immune system modulations favor the dev...

To determine the changes in left ventricular volume and their time course during exercise we studied 30 runners. Left ventricular end-diastolic and end-systolic volumes were measured from biapical two-dimensional echocardiograms recorded during graded upright bicycle exercise. The validity of this echocardiographic technique was assessed by comparing measurements at rest and exercise with resul...

PURPOSE This study compares the training characteristics and the physical profiles of top-class male and female Kenyan long-distance runners. METHOD The subjects were 20 elite Kenyan runners: 13 men (10-km performance time: 10-km performance time of 28 min, 36 s +/- 18 s) and 7 women (32 min, 32 s +/- 65 s). The male runners were separated into high-speed training runners (HST: N = 6) and low...

The aim of this study was to analyze the injury incidence in young trail runners according body region, type, mode onset, and moment occurrence, both total detailed by sex. Thirty-five male sixteen female elite runners, aged between 15 22 years, completed a questionnaire regarding last 2 years. Comparison proportions within groups (all, male, runners) (male vs. computed using z Fisher’s exact t...

Elevation of creatine kinase (CK) in serum after exertion is a reliable marker of skeletal muscle injury. Limited data exist on CK levels in conditioned athletes after endurance training and competition. Serum CK was measured by a kinetic UV method (normal < 100 U/L) in 15 long distance runners before (pre-race), 24 hours after (post-race) and four weeks following (post-race) the 1979 Boston Ma...

In this paper, we study dynamic stability during running, focusing on the effects of speed, and the use of a leg prosthesis. We compute and compare the maximal Lyapunov exponents of kinematic time-series data from subjects with and without unilateral transtibial amputations running at a wide range of speeds. We find that the dynamics of the affected leg with the running-specific prosthesis are ...

There is considerable inter-individual variability in self-selected intensity or running speed. Metabolic cost per distance has been recognized as a determinant of this personal choice. As biomechanical parameters have been connected to metabolic cost, and as different running patterns exist, we can question their possible determinant roles in self-selected speed. We examined the selfselected s...

BACKGROUND: This study examined the changes in participation, performance and age of East African runners competing in half-marathons and marathons held in Switzerland between 2000 and 2010. METHODS: Race times, sex, age and origin of East African versus Non-African finishers of half-marathon and marathon finishers were analyzed. RESULTS: Across time, the number of Kenyan and Ethiopian finisher...

PURPOSE Walking is purported to reduce the risk of atrial fibrillation by 48%, whereas jogging is purported to increase its risk by 53%, suggesting a strong anti-arrhythmic benefit of walking over running. The purpose of these analyses is to compare incident self-reported physician-diagnosed cardiac arrhythmia to baseline energy expenditure (metabolic equivalent hours per day, METhr/d) from wal...

OBJECTIVES To identify physical activity that is beneficial for the maintenance of bone strength with increasing age by examining the relation between bone mineral density (BMD) and chronic endurance training in men. BMD at the proximal femur, its subregions, and the lumbar spine, and serum testosterone were compared between two groups of long distance runners with more than 20 years of trainin...