Heart rate variability (HRV) is a physiological phenomenon denoting inconstancy of the interval between heart beats. Power spectrum analysis of heart rate variability (HRV-PSA) is as a non-invasive tool, which is currently used for a variety of purposes, such as quantification of autonomic modulation during exercise and recovery, assessment of autonomic changes associated with the short-term an...

Zentall and Singer (2007a) hypothesized that our failure to replicate the work-ethic effect in pigeons (Vasconcelos, Urcuioli, & Lionello-DeNolf, 2007) was due to insufficient overtraining following acquisition of the high- and low-effort discriminations. We tested this hypothesis using the original work-ethic procedure (Experiment 1) and one similar to that used with starlings (Experiment 2) b...

OBJECTIVE To examine different hormonal responses to heavy endurance training and overtraining in female athletes. DESIGN Submaximal and maximal treadmill tests, self-report mood measures, and stress hormone analyses were repeated at baseline, after 4 weeks and at the end of 6 to 9 weeks of experimental intensive training and after 4 to 6 weeks of recovery. SUBJECTS Fifteen healthy female e...

PURPOSE To examine the excessive reactive oxygen species (ROS) mediated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and the combined effect of glutamine supplementation and diphenyleneiodonium (DPI) on the function of neutrophils induced by overtraining. METHODS Fifty male Wistar rats were randomly divided into 5 groups: control group (C), overtraining group (E), DPI-admini...

The influence of overtraining on the magnitude of fear-conditioning deficits produced by neurotoxic lesions of the basolateral amygdala (BLA) was examined. Either 1 d before or 1 week after the administration of neurotoxic BLA lesions, rats received either 1 or 25 conditioning trials consisting of the delivery of unsignaled foot shock in a novel observation chamber; freezing served as the measu...

Performance on perceptual tasks usually improves with training. However, too much consecutive training can be detrimental. Repeated within-day testing or overtraining demonstrates the detrimental effects this has on perceptual learning. Consolidation of learnt information during sleep has the power to prevent such deficits in learning. However, little is known regarding the role of wakeful cons...

This review discusses the overtraining syndrome which is characterized by fatigue and underperformance precipitated by stress of training. Other stresses, depression and an increased susceptibility to infections may be important. Treatment requires rest and a stress management program over 3 months.

The coach and interdisciplinary sports science and medicine team strive to continually progress the athlete's performance year on year. In structuring training programmes, coaches and scientists plan distinct periods of progressive overload coupled with recovery for anticipated performances to be delivered on fixed dates of competition in the calendar year. Peaking at major championships is a c...

The chronic fatigue syndrome is characterised by a fatigue that is disproportionate to the intensity of effort that is undertaken, has persisted for 6 months or longer, and has no obvious cause. Unless there has been a long period of patient- or physician-imposed inactivity, objective data may show little reduction in muscle strength or peak aerobic power, but the affected individual avoids hea...

Traditionally, biomarkers have been of interest in sports in order to measure performance, progress in training and for identifying overtraining. During the last years, growing interest is set on biomarkers aiming at evaluating health-related aspects which can be modulated by regular physical activity and sport. The value or concentration of a biomarker depends on many factors, as the training ...