Gender differences in physical and psychological stress responses among college judoists undergoing weight reduction

Gender-related differences in anthropometry, blood biochemistry, psychological parameters, and energy intake during prematch weight reduction were studied in 22 men and 7 women college judoists who lost weight by combining judo training, restricting food and fluid, and sweating. Body weight (BW) decreased significantly by 2.2 ± 1.4 kg in men and 2.0 ± 1.4 kg in women 2 weeks after weight reduction started - not significantly different. Body fat, relative body fat and total energy intake also decreased significantly in both groups 2 weeks after weight reduction started. Lean body mass decreased significantly 2 weeks after weight reduction started only in men. Men had significantly decreased blood lipids, immunoglobulins, complements, hematocrit, white blood cell count, and serum electrolytes, and significant increases in blood uric nitrogen, creatinine, and hemoglobin, while women showed no such changes. The score for vigor in the Profile of Mood States (POMS) decreased in both groups 2 weeks after weight reduction started, but with no statistically gender difference. In women, scores for anxiety in the State-Trait Anxiety Inventory (STAI) and confusion in POMS increased significantly. Although the men and women had the same BW reduction, significant physical stress response was seen only in men, and psychological stress due to weight reduction and mental pressure of an upcoming competition were seen more in women.