In thermoneutral conditions with identical work tasks, women generally have higher muscular activity and higher prevalence of musculoskeletal disorders of the neck and upper extremity compared to men. The objective of this study was to investigate the effect of gender on cooling-induced changes on muscular activity during 2 hours of repetitive manual work at the exposures of 19 ordm;C (thermoneutral, TN) and 4 ordm;C (cold, C). There were eight men and eight women as test subjects. Their physical characteristics were (men/women): age 254 / 233 years, height 1795 / 1634 cm, body mass 7512 / 574 kg and body fat 14.25.0 / 24.33.3 %. Each subject participated once to thermoneutral and cold conditions in a random order. Muscular activity was studied in eight muscles in upper extremity and the shoulder region by surface electromyography. Rectal and skin temperatures (from 15 sites) were measured continuously during the study. During the work at C, mean skin temperature was lower both in men and women compared to work at TN (p<0.05). Women had 0.7 ordm;C and 0.5 ordm;C lower mean skin temperature compared to men at C and TN, respectively (p<0.05). Muscular activity in upper extremity and the shoulder region was higher in women compared to men: 6–57 % higher at C and 8–70 % higher at TN (not significant - p<0.05). Interestingly, cooling increased muscular activity more in men (3.6–30.4 %) compared to women (2.3–15.1 %) although the level of muscular activity in men remained still lower than in women. In conclusion, repetitive work at C increases muscular activity, in both genders and especially in men, compared to similar work at TN. The observed gender differences in muscular activity should be considered when evaluating work promotion in cold conditions.