0000000000951777
AUTHOR
Mikko Koivu
Association with physical fitness, serum hormones and sleep during a 15-day military field training.
The present study aimed to investigate the association between physical fitness, sleep duration and hormonal responses during a 15-day military field training (MFT). The purpose of MFT was to practice offensive manoeuvres in a countryside area. Nine army officers volunteered to participate, and their daily working routine mainly consisted of tasks in the headquarters that required on-call-duty at all times. Physical fitness and body composition were measured just before MFT. Serum testosterone (TES) and cortisol (COR) concentrations and sex-hormone-binding globulin (SHBG) were measured before MFT, as well as 8 and 15 days after the beginning of MFT. Heart rate (HR) was recorded for approxim…
Heart Rate Variability Recordings are a Valid Non- Invasive Tool for Evaluating Soldiers’ Stress
Heart Rate Variability Recordings are a Valid Non- Invasive Tool for Evaluating Soldiers’ Stress The purpose of the present study was to investigate physiological responses and to evaluate heart rate variability as a non-invasive stress indicator during a 72-hour military field training (MFT). Ten healthy male soldiers (age 20 ± 1 yr.) participated in MFT. They slept approximately 2 h/day and ate only army field rations. During MFT, the soldiers’ mean (±SD) energy expenditure was 4646 ± 674, energy intake 2200 ± 326, and energy deficit (ED) 2405 ± 890 kcal⋅day-1.Throughout the entire training period, serum total testosterone (TES) reduced from 19.0 ± 3.0 to 12.6 ± 6.2 nmol⋅l-1 (p<0.001)