Manabu Totsuka

Effect of disuse on the ultrastructure of the achilles tendon in rats

SummaryWe examined the influence exerted, through disuse of the hindlimb, on the collagen fibres of the achilles tendon in rats. With disuse the body mass decreased by 28%, and the mass of soleus muscle decreased by 20%. A decrease in the surface area and diameter was observed in the experimental group when compared to the control group. A histogram of the collagen fibres showed a decrease of the thick fibres in the experimental group. The maximum surface area of collagen fibres in the experimental group was seen to be only 43% of that of the control group. These results showed a decrease in the thickness of the collagen fibres of the achilles tendon through disuse. This seemed to suggest that resistance to tension is decreased by disuse.

Adverse effects of energy restriction on myogenic enzymes in judoists

In this study, we examined the effects of weight reduction by restricting energy intake on muscle function and serum concentrations of myogenic enzymes in judoists. Twenty-seven male judoists aged 19.3±0.6 years (mean±s) were divided into three groups based on the extent of body weight reduction: high weight reduction (height 1.70±0.05 m, body mass 78.5 ±13.6 kg), low weight reduction (height 1.70±0.05 m, body mass 80.7±13.1 kg) and a group that maintained body weight while continuing to perform exercise training (height 1.78± 0.07 m, body mass 78.7±8.8 kg). Body composition, blood biochemistry, energy intake and anaerobic power were assessed on four occasions: 20 days (baseline data), 4 days and 1 day before and 7 days after competition. Compared with baseline, body mass and fat-free mass were significantly lower 1 day before competition in the high and low weight reduction groups (both P <0.01); these changes persisted for 7 days after competition in the high weight reduction group. Serum creatine kinase was significantly elevated 1 day before competition in all groups (all P <0.05), and remained higher 7 days after competition in both the high and low weight reduction groups. Compared with baseline, maximal anaerobic power was significantly lower 1 day before competition only in the high weight reduction group (P <0.01). Our results suggest that energy restriction in addition to intense exercise training before major competition has an adverse effect on anaerobic power and elevates serum creatine kinase concentration, leading to an impairment of muscular function and an increased susceptibility of muscle tissue to injury.

Effects of intense exercise on the physiological and mental condition of female university judoists during a training camp

Abstract To clarify the physical and mental fatigue caused by intense exercise and the relationship between the two types of fatigue, we examined changes in anthropometric and biochemical variables, neutrophil function, and the Profile of Mood States (POMS) questionnaire in 13 female university judoists attending a one-week training camp. Blood glucose, total cholesterol, haemoglobin, leukocyte count, IgG, and phagocytic activity all decreased after the training camp compared with baseline (P ≤ 0.046). Aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and neutrophil oxidative burst activity increased after the training camp (P ≤ 0.007). Of the POMS scores, that for Fatigue increased after the training camp (P = 0.041) and that for Vigour decreased (P = 0.042). The changes in several POMS scores correlated with the changes in blood biochemical variables. In particular, the change in Total mood disturbance was negatively associated with changes in myogenic enzymes (P ≤ 0.032). Our results suggest that intense exercise during training camps for female judoists leads to the appearance and accumulation of mental and physical fatigue, which are related to each other.

The effects of a two-hour judo training session on the neutrophil immune functions in university judoists

The present study examined the effects of judo training on neutrophil and related functions. We measured and studied changes in the neutrophil and its related functions in 22 male university judoists immediately before (Pre values) and immediately after (Post values) a 2 h training session: reactive oxygen species (ROS) production capability, phagocytic activities (PA) and serum opsonic activity (SOA). Neutrophil count in whole blood, myogenic enzymes (creatine kinase, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase), immunoglobulins (IgG, IgA and IgM) and complements (C3 and C4) in serum were also measured. The Post values of the neutrophil count, myogenic enzymes and IgG increased significantly compared with the Pre values. ROS production capability and SOA also significantly increased following training, although PA showed a slight decrease (but not statistically significant). Taking the findings of our previous studies into consideration, three major neutrophil or related functions, namely ROS production capability, PA and SOA, might compensate for each other to maintain the overall integrity of the neutrophil immune function, in that ROS and SOA increased to compensate for the slight decrease in PA, or PA slightly decreased to compensate for the increase in ROA and SOA after exercise.

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 significandy different. Body fat, relative body fat and total energy intake also decreased significandy in both groups 2 weeks after weight reduction started. Lean body mass decreased significandy 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 significandy. 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.