Evaluation of explosive strength ability of the upper body for athletic throwers

Physical fitness evaluation of throwing athletes has been performed based on measurement items for the purpose of power evaluation of the lower limbs and whole body; however, the method for assessing the muscle strength and exertion of the upper body has not been acknowledged extensively. The purpose of this study was to examine the effectiveness of the evaluation of the explosive muscle performance of the upper body of an athlete using several measurement parameters, including push up jump (PJ), countermovement push up (CMPU) flight time, medicine ball throw (MBT), countermovement medicine ball throw, and one repetition maximum of the bench press (BP-1RM). The relationship between these measurement items and athletic performance as determined using the IAAF score was examined. Eleven male athletes training on a daily basis were enrolled. A significant positive correlation between MBT and athletic performance was observed, indicating the usefulness of physical fitness evaluation in athletes. Conversely, PJ and CMPU were not associated with athletic performance, suggesting that these parameters may be negatively affected by the subject’s weight. Further, BP-1RM did not show a significant correlation with athletic performance, owing to the fact that the exertion characteristics of one repetition maximum do not reflect the shrinkage rate of the muscle required for throwing. It is recommended that athletes select an event wherein their weight positively affects the competitive ability and does not affect measurement parameters. Further, explosive muscle performance without counter movements maybe incorporated into the physical fitness assessment of athletes

Cardiorespiratory fitness and the incidence of type 2 diabetes: a cohort study of Japanese male athletes

BACKGROUND: In Japan, although the incidence of overweight (BMI ≥ 25) is still low compared with that in Europe and the United States, the prevalence of type 2 diabetes has increased over the last 15 years,. In both Japanese and Caucasian populations it has been reported that a high level of cardiorespiratory fitness protects against the development of type 2 diabetes. However, there are no reports focused specifically on athletes that investigate whether high cardiorespiratory fitness at a young age can prevent disease later in life. We examined the relationship between cardiorespiratory fitness at a young age and the development of type 2 diabetes in Japanese athletes using a cohort study. METHODS: The cardiorespiratory fitness of male alumni of the physical education department of Juntendo University, as measured by stored data of a 1,500-m endurance run in college (1971–1991) was compared with their incidence of type 2 diabetes as determined by follow-up questionnaires (2007–2009). This study used Cox’s proportional hazards models and adjusted for age, year of graduation, BMI, smoking, and sports club participation at college age. RESULTS: We collected data on cardiorespiratory fitness at college age and medical history survey data during 2007–2009 from 570 male alumni. The median follow-up period was 26 years (IQR: 23–29 years), and 22 men had developed type 2 diabetes. An inverse relationship was observed between incidence of type 2 diabetes and level of cardiorespiratory fitness at time of college after adjustment for age, year of graduation, BMI, smoking, and sports participation. The adjusted hazards ratio and 95% CI by category (low, medium, and high) were 1.00 (reference), 0.40 (0.14–1.13) and 0.26 (0.07–1.00) (p = 0.03 for trend). CONCLUSIONS: A high level of cardiorespiratory fitness at a young age can help prevent type 2 diabetes later in life

Effects of Yellow-Tinted Lenses on Visual Attributes Related to Sports Activities and Daily Life in Late Middle-aged Adults

The purpose of this study was to clarify the effects of colored lenses on the visual performance of middle-aged people. The subjects were 19 middle-aged people with a mean age of 57.4 ±6.0 years. Five different functional lenses were used in the experiments: colorless lenses and four colored lenses (Light-yellow, Dark-yellow, Light-gray, and Dark-gray). Using each lens type, contrast sensitivity, depth perception, hand–eye coordination, dynamic visual acuity, and visual acuity/low-contrast visual acuity were measured. Visual acuity/low-contrast visual acuity was measured under the four conditions of Evening, Evening + Glare, Day, and Day + Glare. Results showed that dynamic visual acuity and depth perception did not differ among the lens types, but hand–eye coordination measurements had a significantly shorter time with the Light-yellow and Dark-yellow lenses than the Dark-gray lenses. Low-contrast visual acuity under Evening and Evening + Glare conditions tended to be lower with the Dark lenses than the Colorless and Light-yellow lenses. The subjects rated the Yellow lenses as bright in a subjective questionnaire evaluation

Effect of sports experiences on competition level and exercise habits in Japanese collegiate athletes

In this study, we investigated the athletic experiences of former collegiate Japanese athletes and compared their competitive results and current exercise habits. A questionnaire survey was completed by physical education or health and sports science students via mail. We sent the survey to 9,507 people; 2,141 questionnaires were returned, accounting for a recovery rate of 22.5%. We collected data on the current level of physical activity, history of sports experiences, and type of athletic competitions participated in from childhood until adulthood. An analysis was conducted on 1,999 participants. The results suggested that Japanese collegiate athletes had continued the same sport since elementary school. Conversely, several recent athletes had multiple-sport experiences and had started sports from an early age. There were no differences in athletic history and athletic performance between some age groups. We believe that having experience in a variety of sports has no adverse effect on athletic performance or exercise habits. In conclusion, compared to the past, the number of collegiate athletes with multiple experiences has increased. However, their experience differed from multiple-sport environments observed outside Japan. It is necessary to reconsider the sports environment of Japanese children in the future.This work was supported by the Joint Research Program of Juntendo University Faculty of Health and Sports Science [no grant number] and Institute of Health and Sports Science & Medicine, Juntendo University [no grant number]

Slightly increased BMI at young age is a risk factor for future hypertension in Japanese men.

Hypertension is developed easily in Asian adults with normal body mass index (BMI) (~23 kg/m2), compared with other ethnicities with similar BMI. This study tested the hypothesis that slightly increased BMI at young age is a risk factor for future hypertension in Japanese men by historical cohort study.The study participants were 636 male alumni of the physical education school. They had available data on their physical examination at college age and follow-up investigation between 2007 and 2011. The participants were categorized into six categories: BMI at college age of <20.0 kg/m2, 20.0-21.0kg/m2, 21.0-22.0kg/m2, 22.0-23.0kg/m2, 23.0-24.0kg/m2, and ≥24.0kg/m2, and the incidence of hypertension was compared.This study covered 27-year follow-up period (interquartile range: IQR: 23-31) which included 17,059 person-years of observation. Subjects were 22 (22-22) years old at graduated college, and 49 (45-53) years old at first follow-up investigation. During the period, 120 men developed hypertension. The prevalence rates of hypertension for lowest to highest BMI categories were 9.4%, 14.6%, 16.1%, 17.5%, 30.3%, and 29.3%, respectively (p<0.001 for trend), and their hazard ratios were 1.00 (reference), 1.80 (95%CI: 0.65-4.94), 2.17 (0.83-5.64), 2.29 (0.89-5.92), 3.60 (1.37-9.47) and 4.72 (1.78-12.48), respectively (p<0.001 for trend). This trend was similar after adjustment for age, year of graduation, smoking, current exercise status and current dietary intake.Slightly increased BMI at young age is a risk factor for future hypertension in Japanese men

A body mass index over 22 kg/m2 at college age is a risk factor for future diabetes in Japanese men.

BACKGROUND:There is a high incidence of type 2 diabetes in Asian adults, even those with a normal body mass index (BMI) (23 kg/m2) at middle age is a risk factor for type 2 diabetes in Asians. In this historical cohort study, we investigated whether a slightly increased BMI at college age was also a risk factor for future diabetes in Japanese men. METHODS:Six hundred and sixty-one male alumni who graduated from a physical education school between 1971 and 1991 and who responded to follow-up investigation between 2007 and 2017 were included in this study. Participants were categorized into four categories: college BMI of <21.0 kg/m2, 21.0-22.0 kg/m2, 22.0-23.0 kg/m2, and ≥23.0 kg/m2, and the incidence and risk ratio of diabetes were compared between groups. RESULTS:The median follow-up period was 32 years (interquartile range, IQR: 27-36), which included 20,983 person-years of observation. Subjects were 22 (22-22) years old at college graduation, and 55 (50-59) years old at the final follow-up investigation. During the study period, 56 men developed diabetes; the prevalence rates for the lowest to highest BMI categories were 4.4%, 7.6%, 10.5%, and 11.3%, respectively, and their adjusted hazard ratios were 1.00 (reference), 1.77 (95% CI: 0.68-4.30), 2.42 (1.00-5.84), and 2.53 (1.06-6.07), respectively (p = 0.03 for trend). CONCLUSION:Our data suggest that a BMI over 22.0 kg/m2 at college age is a risk factor for diabetes later in life in Japanese men

Hazard ratio for hypertension according to BMI (quartiles).

<p>Hazard ratio for hypertension according to BMI (quartiles).</p

Multivariable adjusted cumulative incidence rate curve for hypertension during the follow-up, according to BMI (six categories).

<p>Multivariable adjusted cumulative incidence rate curve for hypertension during the follow-up, according to BMI (six categories).</p

Baseline characteristics of study subjects according to BMI in former male college athletes.

<p>Baseline characteristics of study subjects according to BMI in former male college athletes.</p

Hazard ratio for hypertension according to BMI (six categories).

<p>Hazard ratio for hypertension according to BMI (six categories).</p