M. Rieu

Changes in blood leucocyte populations induced by acute maximal and chronic submaximal exercise

SummaryAbsolute (×103·mm−3) or relative (%) numbers of blood leucocyte types (monocytes, lymphocytes, neutrophils) and lymphocyte subsets (T11+, T4+, T8+, B1+, and NKH1+) reacting with specific monoclonal antibodies were determined at rest, immediately after maximal exercise on a treadmill, in six controls (C), and in six young cyclists before training (BT) and after 5 months of training (AT). Maximal exercise significantly increased the absolute number (mobilization) of virtually all the types of leucocytes and subsets of lymphocytes in C, BT and AT subjects. In these subjects mobilization of natural killer cells (NKH1+) and cytotoxic/suppressor T lymphocytes (T8+) was greater than mobilization of the other leucocyte types and lymphocyte subsets; however, maximal exercise induced no significant changes in the relative numbers of any leucocyte types and lymphocyte subsets, except in the case of T4+ lymphocytes in AT cyclists. Chronic submaximal exercise induced increased mobilization of neutrophils and decreased mobilization of lymphocytes during maximal exercise, except in the case of B lymphocytes (B1+) and NKH1+ cells, and decreases in the absolute and relative number of neutrophils at rest. It remains to be seen how these results can explain the modifications of leucocyte activities noted in vitro after isolated or chronic exercise.

Effect of physical exercise on adoptive experimental auto-immune encephalomyelitis in rats.

The aim of the study was to determine whether different programmes of exercise influence adoptive monophasic experimental auto-immune encephalomyelitis (adoptive EAE), a paralytic disease mediated by T-cells. Adoptive EAE was induced by the transfer of activated encephalitogenic T-lymphocytes into syngeneic recipients (Lewis rats, n = 85) and its development was followed by two independent observers. The results showed that 2 days of severe exercise (250 and 300 min) performed after the adoptive transfer of EAE slightly delayed the onset of the disease (P < 0.008) and the day of its maximal severity (P < 0.016) without affecting the overall severity of the disease. When this programme of exercise was performed before the cell transfer, it had no effect (P > 0.05). Two more moderate exercise programmes (5 × 120 min of running at constant speed or 5 × 60 min of running at variable speed, 5 consecutive days) performed between the adoptive transfer and the onset of the disease did not modify the development of the clinical signs of adoptive EAE (P >0.05). These results showed that severe exercise slightly influenced the effector phase of monophasic EAE and confirmed that physical exercise performed before the onset of experimental auto-immune diseases did not exacerbate the clinical signs.

Blood lactate accumulation in intermittent supramaximal exercise

SummaryBlood lactate accumulation rate and oxygen consumption have been studied in six trained male runners, aged 20 to 30 years. Subjects ran on a treadmill at a rate representing 172±5%

Effect of physical exhaustion and glucocorticoids (dexamethasone) on T-cells of trained rats

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Plasticity of skeletal myosin in endurance-trained rats (I). A quantitative study

for four 45 s sessions, separated by 9 min rest periods. Oxygen consumption was measured throughout. Blood lactate was determined in samples taken from the ear and

Effect of previous supramaximal work on lacticaemia during supra-anaerobic threshold exercise

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