Journal of Sports Medicine & Doping Studies

The aim of this study was to determine whether there are any differences in hamstring strength indices of isokinetic concentric and eccentric peak torques at 60 deg/sec and 180 deg/sec between hamstring injured (left / non dominant) and non-injured (right / dominant) leg in a hamstring-injured athlete. A 25-year-old male recreational athlete who had hamstring injury, grade 2, twice in the past took part in the present case study. Hamstring concentric and eccentric peak torques were tested at two velocities: 60 and 180 deg/sec. The only difference was found in concentric peak torque at 60 deg/sec. Future well - designed studies are needed to find out whether there is a relationship between strength testing and hamstring muscle injury.

Chess is a competitive sport in the classical meaning of the word. One of the most important factors for chess and sport competence is the accumulated time of training. In order to obtain a high level of competence, chess players and athletes alike must spend up 10 years of specific training.
In chess and classical sport energy needed for brain activity is first derived from glycogen stores in brain, muscles and liver and later from adipose tissue. Both, chess and classical sport rely on shared energy from glycogen and fat. When the brain needs additional energy, muscles and liver share energy with the brain. When muscles need additional energy, brain complies with the request of muscles. Energy expenditure, O₂ uptake and CO₂ production during chess games are similar to those obtained during a marathon. Mental and physical fatigue begin with similar metabolic states: deprivation of glycogen. During competitive chess, athletes must be in good physical condition.
Mental profiles of chess players and other athletes correlate with processes such as attention, conflict control, memory, motivation and recognition.
In chess there exists no gender-specific excellence; glycogen availability, however, is less developed in female chess players.
In chess and in classical sports, the brain, spinal cord, nerves and muscles cooperate in complete harmony. The brain commands everything: in chess the figures, in sport the cellular receptors (baro-, lactate-, gluco-, metabo-, chemo-, thermo-, respiratory-) “send” signals via eyes or metabolic changes to the brain. The brain then decides, what to do: in chess, the player moves a figure; in sports, muscles react according to demand.
Physical exercise or chess must be defined by a motor activity completely controlled by the central nervous system (CNS) in combination with a specific competence. In chess as well as in physical exercise, physical stress prepares brain to cognitive stimulation.
With respect to biochemical, physiological, neuronal and psychological aspects, chess is equals classical physical exercise and must be recognized as sport.

Essential elements of Myalgic Encephalomyelitis (ME) are muscle (weakness) and tenderness, cognitive deficits, neurological impairments, especially of cognitive, autonomic and sensory functions, but above all, post-exertional“malaise”: a prolonged increase of symptoms after a minor physical and mental exertion.