Asian Journal of Sports Medicine
Volume:4 Issue: 4, Dec 2013

The purpose of this study was to compare the effects of high، moderate and low intensity plyometric exercise on the post-exercise systolic and diastolic blood pressure and heart rate responses. Ten healthy normotensive men (age، 21. 1±0. 9 years; height، 175. 8±6 cm; and body mass، 69. 1±13. 6 kg) volunteered to participate in this study and were evaluated for three non-consecutive days in depth jump exercise from 20-cm box (low intensity [LI])، 40-cm box (moderate intensity [MI]) and 60-cm box (high intensity [HI]) for 5 sets of 20 repetitions. After each exercise session، systolic blood pressure (SBP)، diastolic blood pressure (DBP) and heart rate (HR) were measured every 10 min for a period of 90 min. No significant differences were observed among post-exercise SBP، DBP and HR when the protocols (LI، MI and HI) were compared. The LI and HI protocols showed greater reduction in SBP at 40th-70th min of post-exercise (~9%)، whereas the LI and MI protocols indicated greater reduction in DBP at 10th-50th min of post exercise (~10%). In addition، the change in the DBP for HI was not significant and the increases in the HR were similar for all intensities. It can be concluded that a plyometric exercise (PE) can reduce SBP and DBP post-exercise and therefore we can say that PE has significant effects for reducing BP and HR or post-exercise hypotension.

Sedentary habits are strongly associated with increase of cardiovascular risk factors. The present study aimed to verify the role of accelerometry in identifying sedentary behavior, and the possible short term positive effect of this intervention on some anthropometric variables in a group of patients with cardiovascular risks factors. To quantify daily Spontaneous Motor Activity (SMA) levels and identify sedentary behavior, an accelerometer was employed, in addition to a simple questionnaire, in a group of overweight, hypertensive subjects. A personalized unsupervised 3 month long physical exercise program was planned. After this time, acceleroometry was again undertaken to analyze the impact of the intervention on some life style parameters, including the number of the steps taken daily, and Physical Activity Level (PAL). In addition, body water balance, weight, and Body Mass Index (BMI) were also evaluated. Assessment of physical activity by accelerometry identifies sedentary behaviors in a larger number of individuals. After three months of regular unsupervised aerobic exercise, PAL improved from 1.56 ±0.1 to 1.68±0.2 with P<0.005, weight (kg) reduced from 85.13 ± 20 to 83.10 ± 19 (P<0.05), BMI from 29.58 to 28.7 (P<0.05). Accelerometry allows to objectify PAL, and can be used to monitor improvement of variables strongly related to cardiovascular risk.

This study was conducted to compare the efficacy and safety of naproxen 500 mg twice daily (BID) versus naproxen 500 mg as needed (PRN) for treatment of ankle sprain. In this seven-day, randomized, parallel group trial, 135 patients with ankle sprain occurring less than 48 hours prior to the first dose of study medication were randomized to receive naproxen 500 mg BID (67 patients) and naproxen 500 mg as needed (PRN) (68 patients). The ankle pain was assessed at rest and on full weight bearing using Numeric Rating Scale (NRS) from 0 (no pain) to 10 (the worst imaginable pain). Ankle swelling was assessed as a 4-point scale ranging from 0 (no swelling) to 3 (severe swelling) rated by the investigator. The primary efficacy end point was the patient’s assessment of ankle pain via NRS and the degree of swelling on day seven. Results showed a significant decrease in pain on weight bearing, pain at rest and the extent of swelling (P<0.001) in both groups, but there was no substantial difference between the two groups (P>0.05) after seven days. Assessing the safety profile of the two different dosing, 13.3 % of the naproxen BID group and 6.7 % of the as needed group had adverse events, showing that the as needed regimen was safer (P<0.001). Results showed that naproxen as needed may reduce the pain and edema of the sprained ankle with no significant difference compared to the BID regimen, while it possesses better safety profile and lower total drug use.

Finswimming is a speed competition sport practiced on the surface or underwater, by using monofins or two fins. In surface events (SF), competitors should surface within 15 m after the start and any turns. The aim of this study was to investigate the gender differences in the aerobic contribution to SF performances in finswimming, using the critical velocity (CV) concept in the analysis. The participants were sixteen monofin swimmers (eight males and eight females; 24±6 years). During a two-day period, participants performed maximal effort swimming at five test distances (100 m, 200 m, 400 m, 800 m and 1500 m), and mean swimming velocity (V) of each distance was calculated. CV was calculated the slope of the regression line between time and distance in the 400 and 800 m SF tests. Although CV was significantly correlated with V800 m and V1500 m for males, it was significantly correlated with V200 m, V400 m, V800 m and V1500 m for females. The present results suggest that although the aerobic performance might contribute to SF performance for events from middle distance (i.e. 200m) to long distance (i.e. 1500m) in female participants, it might contributes to the long distance SF performances in male participants.

Investigate the physiological responses and rating of perceived exertion (RPE) in elite karate athletes and examine the relationship between a subjective method (Session-RPE) and two objective heart-rate (HR)-based methods to quantify training-load (TL) during international karate competition. Eleven karatekas took part in this study, but only data from seven athletes who completed three matches in an international tournament were used (four men and three women). The duration of combat was 3 min for men and 2 min for women, with 33.6±7.6 min for the first interval period (match 1−2) and 14.5±3.1 min for the second interval period (match 2−3). HR was continuously recorded during each combat. Blood lactate [La-] and (RPE) were measured just before the first match and immediately after each match. Means total fights time, HR, %HRmax, [La-], and session-RPE were 4.7±1.6 min, 182±9 bpm, 91±3%, 9.02±2.12 mmol.L-1 and 4.2±1.2, respectively. No significant differences in %HRmax, [La-], and RPE were noticed across combats. Significant correlations were observed between RPE and both resting HR (r=0.60; P=0.004) and mean HR (r=0.64; P=0.02), session-RPE and Banister training-impulse (TRIMP) (r=0.84; P<0.001) and Edwards TL (r=0.77; P<0.01). International karate competition elicited near-maximal cardiovascular responses and high [La-]. Training should therefore include exercise bouts that sufficiently stimulate the zone between 90 and 100% HRmax. Karate coaches could use the RPE-method to follow competitor’s competition loads and consider it in their technical and tactical training.

This study investigated the agreement of four anthropometric-based measurements including weight-for-height (WH), body mass index-for-age (BMI), mid-upper arm circumference-for-age (MUAC), and triceps skinfold thickness-for-age (TST) to identify underweight and overweight children and adolescents. Two data sets were used in this research. The first one was a multistage random sample of 2397 healthy school children in pre-pubertal stage in Shiraz. The second data set consisted of 487 healthy students in pubertal stage and 558 students in post-pubertal stage. The parametric LMS method was used to construct reference centiles curves for each measure. The Kappa statistic was applied to examine the pairwise agreement of the four indices for detecting thinness and obesity. Generally, the pairwise agreement of adiposity measures was higher for identifying obesity than thinness. There was an excellent agreement between WH and BMI for detecting both thin and obese children in almost all subgroups. MUAC had an excellent agreement with BMI in pre-pubertal individuals. However, TST had a weak agreement with the other three indices for detecting thinness and weak to good agreement for classification of obesity. Based on our findings, the performance of the four anthropometric-based measurements varied by sex and maturity level. Therefore, researchers should be more careful while using these indicators to define thin and obese individuals in different subgroups. MUAC as a simple and low-cost screening tool can also be used as an alternative to BMI for obesity assessment among pre-pubertal groups. However, TST should be used cautiously with the other body composition indices.

The study of the right ventricular (RV) chamber has been recently improved by use of the method 3D. In young asymptomatic trained athletes, RV is not routinely investigated if not in suspected disease. This study is designed to test if the method 3D compared to 2D, adds information to study of RV morphology and function, in the early stages of myocardial remodeling of a group of young athletes. The RV chamber function was assessed in 25 young trained athletes (20 soccers and 5 basketball) aged 20±3 yrs compared to 20 sedentary controls by 2D-AC and 3D-RV methods (TomTec), measuring RV diastolic (RVDV) and systolic (RVSV) volumes or ejection fraction (EF). 3D RV volumes were slightly higher in athletes than the 2D volumes in presence of lower EF values, despite not significantly than in sedentary. Significant differences were conversely found comparing 3D systolic and diastolic RV volumes and 2D-AC volumes within each group with higher values in athletes (RVDV: P=0.001 for athletes and P<0.001 for sedentary, and RVSV: P<0.04 for athletes and P<0.001 for sedentary). Despite the found EF values were substantially similar, the morphological assessment of the initial modifications of this chamber of the young''s “athlete’s heart”, results to be more accurate using the 3D method than 2D. The clinical implication of this aspect could be of interest in case of difficulty in drawing a clear diagnosis of any RV chamber disease in young athletes.

Fatigue of trunk muscle contributes to spinal instability over strenuous and prolonged physical tasks and therefore may lead to injury, however from a performance perspective, relation between endurance efficient core muscles and optimal balance control has not been well-known. The purpose of this study was to examine the relationship of trunk muscle endurance and static balance. Fifty male students inhabitant of Tehran university dormitory (age 23.9±2.4, height 173.0±4.5 weight 70.7±6.3) took part in the study. Trunk muscle endurance was assessed using Sørensen test of trunk extensor endurance, trunk flexor endurance test, side bridge endurance test and static balance was measured using single-limb stance test. A multiple linear regression analysis was applied to test if the trunk muscle endurance measures significantly predicted the static balance. There were positive correlations between static balance level and trunk flexor, extensor and lateral endurance measures (Pearson correlation test, r=0.80 and P<0.001; r=0.71 and P<0.001; r=0.84 and P<0.001, respectively). According to multiple regression analysis for variables predicting static balance, the linear combination of trunk muscle endurance measures was significantly related to the static balance (F (3,46)=66.60, P<0.001). Endurance of trunk flexor, extensor and lateral muscles were significantly associated with the static balance level. The regression model which included these factors had the sample multiple correlation coefficient of 0.902, indicating that approximately 81% of the variance of the static balance is explained by the model. There is a significant relationship between trunk muscle endurance and static balance.

To investigate the possibility of a delay in the super-compensation phase due to aging in jump practice. This study evaluated records in three phases (approximately every five years) of a man who had been participating in Masters Athletics for over 20 years. After correcting for air temperature, which would influence the distance on a standing five-step jump using simple regression analysis, the performance curve of the super-compensation phase was calculated at each phase by curvilinear estimation to assess the relationship between the training interval and distance on the standing five-step jump. A peak distance on the standing five-step jump was achieved after a training interval of 60 hours in the first phase; 75 hours in the second phase; and 88 hours in the third phase. That is, the peak distance tended to delay with aging. It may be suggested that the super-compensation period would be delayed by aging in jump practice. We would like master athletes to refer this result and improve their performance.