Anthony T. Nakazawa

Oxygen uptake, heart rate, and blood lactate responses during and following karate training

PURPOSE The purpose of this study was to examine whether each exercise and an entire karate training session can achieve: 1) accepted training intensity thresholds for effective aerobic capacity training, 2) energy expenditure (EE) thresholds for total body mass and fat weight loss, and 3) elevation in excess postexercise oxygen consumption (EPOC). METHODS We investigated physiological responses during five types of karate training: basic techniques without (S-Basics) and with (M-Basics) movements, sparring techniques without (TECH I) and with (TECH II) an opponent, and kata. RESULTS The mean percent of maximal oxygen uptake (%VO2max) and HR (%HRmax) for S-Basics were below the accepted threshold (60% of HRmax or 50% of VO2max) and for M-Basics, TECH I and TECH II were above the threshold for increasing VO2max. For kata and the entire 70 min of karate training, the mean %HRmax were slightly above the threshold, and %VO2max were slightly below the threshold. The mean EPOC measured for 5 min immediately following 70 min of karate training did not differ from the resting VO2. The mean EE resulting from 70 min of karate exercise and EPOC were 2355.4+/-316.3 kJ and 38.8+/-32.7 kJ, respectively. CONCLUSIONS Although the training intensity of karate exercises studied was moderate and the effects of karate training on EPOC were minimal, the mean value of EE was well above the accepted threshold for total body mass and fat weight loss.

Nutrient intake, serum lipids and iron status of colligiate rugby players

BackgroundThere are two main playing positions in rugby (backs and forwards), which demonstrate different exercise patterns, roles, and physical characteristics. The purpose of this study was: 1) to collect baseline data on nutrient intake in order to advise the athletes about nutrition practices that might enhance performance, and 2) to compare serum lipids, lipoproteins, apolipoproteins (apo), lecithin:cholesterol acyltransferase (LCAT) activity, and iron status of forwards and backs.MethodsThe sporting group was divided into 18 forwards and 16 backs and were compared with 26 sedentary controls. Dietary information was obtained with a food frequency questionnaire.ResultsThere were significant differences among the three groups. The forwards had the highest body weight, body mass index, percentage of body fat (calculated by sum of four skinfold thicknesses), as well as the highest lean body mass, followed by the backs and the control group. The mean carbohydrate intake was marginal and protein intake was lower than the respective recommended targets in all three groups. The mean intakes of calcium, magnesium, and vitamins A, B1, B2, and C were lower than the respective Japanese recommended dietary allowances or adequate dietary intakes for the rugby players. The forwards had significantly lower high-density lipoprotein cholesterol (HDL-C) and HDL2-C than the backs and had significantly higher apo B and LCAT activity than the controls. The backs showed significantly higher HDL-C, HDL3-C, low-density lipoprotein cholesterol, and apo A-I, and LCAT activity than the controls. Four forwards (22%), five backs (31%), and three controls (12%) had hemolysis. None of the rugby players had anemia or iron depletion.ConclusionThe findings of our study indicate that as the athletes increased their carbohydrate and protein intake, their performance and lean body mass increased. Further, to increase mineral and vitamin intakes, we recommended athletes increase their consumption of green and other vegetables, milk and dairy products, and fruits. The forwards showed more atherogenic lipid profiles than the backs, whereas the backs showed not only anti-atherogenic lipid profile, but also showed more atherogenic lipid profile relative to the control group. Additionally, our study showed none of the rugby players experienced anemia and/or iron depletion.