ABSTRACT
The present study was performed to ascertain the annual changes in the number and nature of traumatic head injuries that occur in high-school rugby matches, and as an exploratory investigation of approaches to improve safety in the future. It was based on injury reports submitted at the time of injury to the Kansai Rugby Football Union between Apr. 2009 and Mar. 2016. The finding was that the mean number of reported cases of traumatic head injury per year during the three pre-amendment years from Apr. 2009 to Mar. 2011 was 18.0, whereas that during the five post-amendment years from Apr. 2012 to Mar. 2016 was 36.2. Of all the traumatic head injuries, those with the highest numbers and proportions of cases for each of the four factors were as follows: (i) occasion of injury: during a match, 115 (48.9%); (ii) condition of the pitch: grass, 105 (44.7%); (iii) school grade: 2, 104 (44.3%); and (iv) cause of injury: tackling, 115 (48.9%). In addition, the odds ratios (ORs) for brain concussion at post-amendment as compared with pre-amendment and for occurrence on grass as compared with on soil were significant 2.83. An exploratory investigation was conducted to clarify whether different factors are associated with the severity of pre- and post-amendment injuries, but no significant ORs were found. In conclusion, the establishment of guidelines related to brain concussion in 2012 increased the number of reports of injuries due to high-school rugby and had a definite effect on prompt treatment of brain concussions.
ABSTRACT
The purpose of this investigation was to determine the effects of daily walking on aerobic work capacity, vital age and other fitness components in middle-aged and elderly walkers. The subjects were thirty-six walkers (average 65.0±8.0 yr, 51-80 yr), whose training period averaged 13.5±9.0 yr. The walkers were significantly greater in maximal oxygen uptake (VO<SUB>2</SUB>max), and oxygen uptake at the lactate threshold (VO<SUB>2</SUB>LT), and were 6.5 yr younger in vital age (VA) than sedentary middle-aged and elderly. These findings suggest that middle-aged and elderly walkers have more favorable profile of aerobic work capacity and of health status when compared to sedentary persons.
ABSTRACT
Although maximal oxygen uptake (VO<SUB>2</SUB>max) or oxygen uptake corresponding to lactate threshold (VO<SUB>2</SUB>@LT) is considered the single best determinant of one's cardio-respiratory endurance or aerobic capacity, the direct measurement of these attributes requires elaborate equipment, trained personnel, special knowledge, and/or a maximal effort on the part of the subject who is tested. In addition, the measurement is time consuming. The current investigation was designed to examine the validity of aerobic capacity estimated from submaximal cycling exercise and field performance tests in the elderly. The subjects tested were 18 sedentary men and women aged 63 to 75 years (69.7±3.4) . Indirect VO<SUB>2</SUB>max tests were selected from those proposed by Astrand and Ryhming, Siconolfi et al., and Margaria et al. (step test), and YMCA. The VO<SUB>2</SUB>max values estimated by these methods, with the exception of the Siconolfi method, were found to have large errors when compared to the errors obtained in previous studies for younger subjects. There were no significant correlations between step test scores and VO<SUB>2</SUB>max and VO<SUB>2</SUB>@LT in the elderly. Correlations of 12-min distance walk with VO<SUB>2</SUB>max (r=.711) and VO<SUB>2</SUB>@LT (r=.714) were significant. Our findings suggest that 12min distance walk be a better aerobic capacity test than other indirect VO<SUB>2</SUB>max tests including Astrand and Ryhming test.
ABSTRACT
Maximal oxygen uptake (Vo<SUB>2</SUB>max) and lactate threshold were measured during an incremental bicycle ergometer test in 40 healthy middle-aged and older runners between 43 and 79 years of age. Although the 10-km run time slowed with increasing age, there were no significant differences in recent training habits or relative amount of body fat between four age groups. However, our cross-sectional data revealed an annual decrement of -0.74 m<I>l</I>/kg/ min/yr, which was significantly greater than that reported in previous studies. Vo<SUB>2</SUB>max values for the runners were greater than those for sedentary men of similar ages by about 50% in each age group. Significant correlations were found between the age at the onset of running training and Vo<SUB>2</SUB>max (r=-0.600, p<0.05) . Vo<SUB>2</SUB>@LT declined significantly but less rapidly with age (r=0.686, p<0.05) than Vo<SUB>2</SUB>max. Both the mean maximal heart rate (HRmax) and HR@LT also declined with age. No significant differences in HRmax were observed between the runners and sedentary men of the respective age groups. Significant correlations were also found between the estimated HRmax and directly measured HRmax (r=0.600) . Neither systolic blood pressure nor diastolic blood pressure during submaximal-maximal exercise were found to increase with age. We suggest that maintenance of a higher lactate threshold in older runners when expressed as a percentage of Vo<SUB>2</SUB>max is attributable to a greater age-dependent decline in Vo<SUB>2</SUB>max with a smaller change in Vo<SUB>2</SUB>@LT.
ABSTRACT
The purpose of this study was to measure the effectiveness of RPE on exercise intensity for senior citizens. A maximum workload test was administered with the use of a bicycle ergometer on older male and female subjects. The results of our study can be summarized as follows:<BR>1. Two trials were performed on separate days. A high correlation coefficient for the first trial and the second trial was found. The reliability for the male group was r=0.76 (p<0.01) and that for the female group r=0.90 (p<0.01) .<BR>2. A correlation range of r=0.55-0.79 (p (0.01) was found for RPE and physiological exercise intensity (which includes oxygen intake and heart rate) . A higher result was found when the relative value was used in the analysis of the oxygen intake and the heart rate instead of the absolute value.<BR>3. Significant correlation coefficients of r=0.63-0.64 (p<0.01) were found for RPE and the work load in terms of watt units.<BR>4. The majority of the physiological variables were statistically determined ; however, there were no correlations between RPE and systolic blood pressure.<BR>In conclusion, based on our study, we have found that RPE and HR ; RPE and %Vo<SUB>2</SUB>max: RPE and watts grouped individually had a high correlation for effectiveness. The only exception in our study was the RPE and the blood pressure group because no correlation was found overall. Therefore, the overall effectiveness of RPE was proven to be quite sensitive even for senior citizens, and as a result RPE can be utilized when exercise is prescribed for evaluatory measurement in senior citizens.