PURPOSE To identify risk factors for stress fracture among young female distance runners. METHODS Participants were 127 competitive female distance runners, aged 18-26, who provided at least some follow-up data in a randomized trial among 150 runners of the effects of oral contraceptives on bone health. After completing a baseline questionnaire and undergoing bone densitometry, they were foll...

Consider the unit circle C and a circular arc A of length l = |A| < 1. It is shown that there exists k = k(l) ∈ N, and a schedule for k runners with k distinct but constant speeds so that at any time t ≥ 0, at least one of the k runners is not in A.

In this investigation, we compared lipid and inflammatory parameters in regular long distance runners with matched sedentary controls. Long distance runners had significantly lower low-density lipoprotein cholesterol and C-reactive protein levels than the control group. This exercise-induced reduction in low-density lipoprotein cholesterol was independent of the decrease in C-reactive protein l...

OBJECTIVES To evaluate common factors associated in the development of acute renal failure (ARF) in Comrades Marathon runners. METHODS This was a retrospective case series of 4 runners hospitalised post-race with ARF in the 89 km 2010 Comrades Marathon. The outcome measures were incidence of analgesic use, levels of creatine phosphokinase (CPK) and degree of electrolyte supplementation (sodiu...

The purpose of this study was to compare the heel pad mechanical properties of runners, who repetitively load the heel pad during training, with cyclists who do not load their heel pads during training. Ten competitive long distance runners and 10 competitive cyclists volunteered for this study. The thickness of the unloaded heel pad was measured using realtime B-mode ultrasonography. A heel pa...

In 219 recreational male runners, we investigated changes in body mass, total body water, haematocrit, plasma sodium concentration ([Na(+)]), and urine specific gravity as well as fluid intake during a 100-km ultra-marathon. The athletes lost 1.9 kg (s = 1.4) of body mass, equal to 2.5% (s = 1.8) of body mass (P < 0.001), 0.7 kg (s = 1.0) of predicted skeletal muscle mass (P < 0.001), 0.2 kg (s...

OBJECTIVES To determine whether acute exercise associated muscle cramping (EAMC) in distance runners is related to changes in serum electrolyte concentrations and hydration status. METHODS A cohort of 72 runners participating in an ultra-distance road race was followed up for the development of EAMC. All subjects were weighed before and immediately after the race. Blood samples were taken bef...

As a potential means to decrease their risk of injury, many runners are transitioning into barefoot running. Habitually shod runners tend to heel-strike (SHS), landing on their heel first, while barefoot runners tend to mid-foot or toe-strike (BTS), landing flat-footed or on the ball of their foot before bringing down the rest of the foot including the heel. This study compared muscle activity,...

To assess left ventricular structure and function at rest and during exercise in endurance athletes, 10 elite marathon runners, aged 28 to 37 years, and 10 matched nonathletes were studied by echocardiography and supine bicycle ergometry. Each athlete's best marathon time was less than 2 h 16 min. Echocardiography was performed at rest, at a 60 W work load and at an individually adjusted work l...