The aim of this study was to investigate the relationship between the frequency of typical Japanese dietary pattern (JDP) meal consumption and nutrient intake in Japanese university athletes. Dietary information was collected on three non-consecutive days using the 24-hour dietary recall method in the summer of 2013 and 2015. JDP meals were defined based on the Japanese Food Guide Spinning Top. A total of 272 (145 males) university athletes were divided into four groups based on their daily frequency of JDP meal consumption: daily consumption was ≤0.67 times in Group I (36 males, 57 females), once in Group II (39 males, 22 females), 1.33 times in Group III (35 males, 21 females), and ≥1.67 times in Group IV (35 males, 27 females). Logistic regression analysis was used to evaluate the odds ratio of not meeting the reference intake value of the dietary recommendation for athletes (DRA) or the recommended daily allowance for Japanese (2015) (RDA). The median JDP meal consumption was once a day. In both males and females, a significant trend was observed in energy intake, which progressively increased in Groups II, III, and IV compared to Group I (p < 0.001 for both genders). The higher the frequency of JDP meal consumption, the higher the intake of both food groups and nutrients. The higher the JDP meal frequency, the lower the risk of not meeting the DRA or RDA. These observations in summer suggest that increasing the frequency of JDP meal consumption may prevent inadequate nutrient intake for Japanese university athletes.
The prevalence of Osgood-Schlatter disease (OSD) and related factors were investigated in junior high school students. The musculoskeletal injuries of 619 students in junior high school in Japan were examined. The incidence of Osgood-Schlatter disease and factors associated with prevalence of the disease were investigated by means of a questionnaire on sports team membership and bone/joint pain, measurement of subjects’ height and weight and any increase, evaluation of the stage of tibial development using a diagnostic ultrasound device, and evaluation of OSD and musculoskeletal injuries. OSD was seen in 4.8% of subjects. It was more common in boys and in the epiphyseal stage of tibial development, coinciding with the growth spurt. The prevalence of OSD was higher in subjects who belonged to a sports team than in those who did not belong to a sports team. The results of multiple logistic regression analysis for factors relating to onset of OSD in junior high school students showed significant associations with gender (male) and weight increase. Individuals in the growth-spurt period have a high risk of OSD, consequently, musculoskeletal examination using ultrasound, as well as exercise coaching aimed to prevent overuse, are important.
In this study, healthy participants aged 30 to 45 years, who do not exercise regularly, were administered black vinegar beverages (containing acetic acid) daily for 7 days and assessed for feelings of physical fatigue following exercise. The study was a randomized, double-blind, placebo-controlled crossover study. The evaluation was conducted mainly using the Visual Analog Scale (VAS), which assesses feelings of physical fatigue, to measure levels of serum creatine kinase (CK). Feelings of fatigue were determined using the VAS with an ergometer before, immediately, and 30 and 60 min after exercise, as well as at bedtime, and the following morning after awaking. Our results showed that 7 days of test beverage (containing 666 mg acetic acid) intake significantly decreased feelings of physical fatigue 30 min following exercise and at bedtime, compared to intake of the placebo beverage (containing 54.8 mg acetic acid). Furthermore, in the test beverage condition, feelings of shoulder stiffness were significantly decreased at bedtime on the day of exercise and the following morning. However, the test beverage had no significant effects on subjective feelings of fatigue or pain in the leg muscles or levels of serum CK after exercise. Our findings suggested that acetic acid may contribute to a more rapid recovery of physical fatigue after exercise.
Increased strain of the iliotibial band (ITB) is a key factor of ITBS aggravation. There are several internal risk factors contributing to increased ITB strain; gender (female), knee malalignment (genu varum > genu valgus), deteriorated muscle strength and/or muscle activation. However, running biomechanics as an inciting movement of ITBS should be included in the clarification of the ITBS mechanism. The purpose of this study was to clarify the change of the ITB strain during running and to identify differences in muscle activity between runners with or without genu varum. A total of 17 healthy recreational women runners [genu varum group (GV) = 8; normal group (N) = 9] volunteered in this study. Participants performed 30 minutes of running, and muscle activity of gluteus maximus (GMAX), gluteus medius (GMED), and tensor fascia latae (TFL) were recorded every 10 minutes of the running. Before and after running, the strain of the ITB and hip muscle strength were measured. The results showed a significantly increased ITB strain in standing after 30-min running for the participants with genu varum alignment. Also, there was a significant difference between the groups. And the muscle activities of the TFL and GMAX in the GV group were greater than those in the N group. These findings indicate that genu varum alignment may induce more tensile stress on the ITB as a result of greater activation of the TFL during running, thus increasing the strain of the ITB.
The present study aimed to examine the associations between cardiorespiratory fitness and muscular strength (both independently and combined) and non-high-density lipoprotein cholesterol (non-HDL-C) concentrations in 652 Japanese children and adolescents (mean ± SD, 11.0 ± 1.5 years). Fasting blood tests were conducted to measure total cholesterol, HDL-C, triglyceride, and low-density lipoprotein cholesterol concentrations. Cardiorespiratory fitness was determined using the 20 m shuttle run test (SRT), and muscular strength was obtained from grip strength (GS) tests. Relative GS, which was defined as absolute GS divided by body mass index (BMI), was computed. Cardiorespiratory fitness was inversely associated with non-HDL-C after adjusting for age, gender, and BMI (β = -0.102, p < 0.05). However, this association was diminished after adjusting for relative GS. In contrast, relative GS was inversely associated with non-HDL-C, and this remained significant even after adjusting for age, gender, BMI, and cardiorespiratory fitness (β = -0.162, p < 0.05). There was a significant interactive effect (20 m SRT*relative GS) on non-HDL-C after adjusting for age, gender, BMI (β = -0.122, p < 0.05). Additionally, combined analysis showed that children and adolescents with both low SRT and GS demonstrate the highest non-HDL-C concentrations compared with their counterparts, suggesting that the effects of cardiorespiratory fitness and muscular strength were additive. In conclusion, enhancing muscular fitness may be a primary target through which non-HDL-C concentrations can be regulated, particularly for children and adolescents with low cardiorespiratory fitness.
We investigated changes in the basic parameter of physiological stress such as catecholamine and heart rate, blood pressure during the ascent of one-day Mt. Fuji hiking via the Fujinomiya Trail. Six Japanese healthy young adult males (age: 21 ± 1 years) volunteered to hike Mt. Fuji (altitude: 3,776 m) located in Shizuoka Prefecture in August 2014. The weather was fine. Heart rate (HR), arterial oxygen saturation (SpO2), blood pressure (SBP/DBP), double product (DP), urinary adrenaline (AD) · urinary noradrenaline (NA) and creatinine (Cr) were measured at a point near sea level (Pre: altitude 9 m) and during the ascent. HR, AD/Cr, NA/Cr and DP at the summit were significantly higher and SpO2 was significantly lower than those of Pre and 5th Station (altitude: 2,400 m). AD/Cr and NA/Cr at the 5th Station were significantly higher than those of Pre (values at starting point near sea level). There was no significant change in SBP and DBP. As a significant positive correlation between changes in the indices of catecholamine (AD/Cr, NA/Cr) and HR, DP was observed during the ascent of one-day Mt. Fuji hiking (p<0.05). It has become obvious that the increase in urinary catecholamine and the index of cardiac overload during the ascent of Mt. Fuji should be derived from an enhancing of adrenergic sympathetic nervous activity by barometric depression, temperature decrease, and increase in exercise intensity. In addition, enhanced adrenergic sympathetic nervous activity was caused by hypobaric hypoxia even at the 5th Station.