[THE WORK DAY, EFFICIENCY AND PRODUCTIVE YEARS OF MEN ENGAGED IN HEAVY PHYSICAL WORK].
D004526:Efficiency; D006801:Humans; D008297:Male; D009787:Occupational Medicine; D010808:Physical Examination; D005082:Physical Exertion
EXERTION; INDUSTRIAL MEDICINE
PRACOVN'I DOBA, V'YKONNOST A PRACOVN'I V EK U FYZICKY T E ZCE PRACUJ'IC'ICH.