Plasma adrenocorticotropin and cortisol responses to submaximal and exhaustive exercise

Abstract

Adrenocorticotropic hormone (ACTH) levels were compared before and after submaximal and exhaustive isotonic exercise in six normally active college students (3 men and 3 women). Each subject participated in three experiments conducted at the same morning hour. Venous plasma was obtained before and immediately after 20-min runs at 65 and 80% of maximal O2 consumption (VO2 max) and after a run of gradually increasing work intensity which resulted in exhaustion (100% VO2 max) in 12.6 +/- 1.3 min. ACTH (mean +/- SE) was 48 +/- 15, 57 +/- 12, and 61 +/- 11 pg/ml before the 65, 80, and 100% VO2 max runs, and increased to 61 +/- 15 (NS), 128 +/- 18 (P less than 0.05), and 292 +/- 72 (P less than 0.05) pg/ml, respectively. Plasma glucose, growth hormone, cortisol, and lactic acid concentrations increased in a similar fashion. Cortisol and ACTH levels were significantly correlated at the higher levels of exertion: r = 0.18 (NS) for the 65% VO2 max run, r = 0.65 (P less than 0.05) for the 80% VO2 max run, and r = 0.64 (P less than 0.05) for the run to exhaustion. Both the change in ACTH with exercise and its postrun concentration were significantly related to the change in plasma lactic acid (r = 0.65, P less than 0.05) and the postrun plasma lactic acid (r = 0.64, P less than 0.05). We conclude that exercise-induced increases in plasma ACTH and their correlation with circulating cortisol depend on the intensity of isotonic exercise. Our observations also suggest that plasma lactic acid may influence ACTH release during exercise.

Interactions of Metabolic Hormones, Adipose Tissue and Exercise

“…[168] The increase in cortisol could lasts 30-60 minutes at a moderate intensity, then the be related to elevation of lactic acid in some way total energy expenditure will range from 200 to 700 stimulating ACTH, [169] increased IL-6, [13] or it is kcal (840-2900kJ). Since the intensity is usually possible that the increased SNS activity results in an moderate, then 40-60% of the energy will be deelevation of NPY in the hypothalamus, resulting in rived from fat.…”

Voluntary wheel running initially increases adrenal sensitivity to adrenocorticotrophic hormone, which is attenuated with long-term training

“…Acutely, this recruitment of energy sources is essential for events, such as physical exercise; however, restoration of the axis is imperative to prevent overexposure to GCs. It has been well established that chronically elevated levels of plasma GCs can lead to the development of a number of harmful pathologies, including impaired insulin signaling, central adiposity, skeletal muscle atrophy, immune suppression, and type 2 diabetes mellitus (6,16,24,33).Exercise is a potent stressor, activating the HPA axis in animals (5, 8 -10, 14, 27) and in humans (13,15,22,30). The effects of regular exercise on diurnal GC levels and adrenal sensitivity to ACTH secretion are unclear.…”

“…Exercise is a potent stressor, activating the HPA axis in animals (5, 8 -10, 14, 27) and in humans (13,15,22,30). The effects of regular exercise on diurnal GC levels and adrenal sensitivity to ACTH secretion are unclear.…”

Lifestyle, stress and cortisol response: Review II

“…Cortisol increases during exercise if the intensity of the exercise exceeds 60% of maximal VO 2 max after more than 1 h 74) . However, conflicting observations were reported in some studies [75][76][77][78][79][80] . No increase in blood cortisol level after exercise at workloads above 70% of VO 2 max81)…”

“…The cortisol response to exercise is determined by threshold intensity [72][73][74][75][76][77][78][79][80][81] . The serum level of cortisol is known to increase when a certain workload is exceeded 72,73) .…”