Endurance tests are the most reliable core stability related measurements

PurposeTo determine the intra-tester reliability of clinical measurements that assess five components related to core stability: strength, endurance, flexibility, motor control, and function.MethodsParticipants were 15 college-aged males who had not suffered any orthopedic injury in the past year. Core strength measurements included eight isometric tests and a sit-up test. The four core endurance tests were the trunk flexor test, trunk extensor test, and bilateral side bridge tests. Flexibility tests included the sit-and-reach test and active range of the trunk and hip joint motions. Proprioception via passive reposition tests of the hips and a single limb balance test on an unsteady platform were used to evaluate core motor control. Functional measurements consisted of a squat test and a single leg hop test for time and distance. Measurements were performed during two data collection sessions with a week's rest between the sessions. Intra-class correlation coefficients were calculated to establish reliability.ResultsThe overall intra-rater reliability for all core stability related measurements ranged from low (ICC = 0.35, left hip reposition) to very high (ICC = 0.98, sit-and-reach). As a group, the core endurance tests were observed to be the most reliable.ConclusionThere are highly reliable tests in each of the five groups. Overall, core endurance tests are the most reliable measurements, followed by the flexibility, strength, neuromuscular control, and functional tests, respectively.     

Effects of Two Systems of Weight Training on Circulorespiratory Endurance and Related Physiological Factors

Abstract

Three groups, two experimental and one control, consisting of 20 college freshmen in each group, were tested doing moderate and all-out exercise on a bicycle ergometer. Selected physiological responses and the circulorespiratory endurance times were measured. An eight-week training period followed during which the experimental groups participated in weight-training programs and the control subjects in archery or bait casting. After training, the tests were again administered.

Though there was an indication of improved circulorespiratory responses by the weight-training groups following training, statistical treatment of the data revealed no significant differences among the three groups in their responses to exercise.     

Effect of a Single Day's Swimming on Selected Components of Athletic Performance

Abstract

The purpose of this investigation was to study the effect of swimming on selected components of athletic performance as measured by the following tests: back strength, leg strength, bicycle ergometer (combination of strength and endurance, but predominantly endurance), and vertical jump (explosive power). Subjects were pretested for three days on each test, after which they participated in 45 minutes of swimming, and performance was tested oh one test one hour after the swim on any given day. A single day's swimming was found to significantly affect the vertical jump, but other performance tests were not affected.     

Cardiorespiratory Adaptations to Training at Specified Frequencies

Abstract

Twenty young male volunteers were randomly assigned to one of four training groups or a control group in a study of the effect of various training frequencies on cardiorespiratory endurance. Training consisted of treadmill running at a rate of seven miles per hour for a ten-minute period. As each subject completed a ten-minute run the grade was increased one percent for the next training period. The group trained for one, two, three or five days per week for five weeks. Improvement was measured by pre- and post-administration of the Balke treadmill test, the Åstrand-Ryhming (A-R) test of physical fitness, the Taylor, Buskirk and Henschel test of maximal oxygen intake, and by maintaining a record of the number of training sessions completed. While the Balke test indicated significantly greater improvement for those in the five-day group, the other methods of measurement favored either the two- or three-day groups. Pre-training correlations among the three tests indicated that the A-R test was significantly related to the Balke and oxygen intake tests but that the latter tests were not related.     

Expediting the Institutional Review Board Process for Exercise Protocols

Abstract

The investigation was conducted to determine the relative effectiveness of three different approaches to health instruction at the college level. Each of three groups of students was taught by one instructional approach: problem solving, lecture, or discussion. Analysis of initial and final measurements of health knowledge, health attitudes, and health interests through the covariance technique and t tests indicated that all three approaches were equally effective in the achievement of instructional outcomes.     

Effects of intermittent sprint and plyometric training on endurance running performance

PurposeThe purpose of this study was to compare the effects of intermittent sprint training and plyometric training on endurance running performance.MethodsFourteen moderately trained male endurance runners were allocated into either the intermittent sprint training group (n = 7) or the plyometric training group (n = 7). The preliminary tests required subjects to perform a treadmill graded exercise test, a countermovement jump test for peak power measurement, and a 10-km time trial. Training included 12 sessions of either intermittent sprint or plyometric training carried out twice per week. On completion of the intervention, post-tests were conducted.ResultsBoth groups showed significant reduction in weekly training mileage from pre-intervention during the intervention period. There were significant improvements in the 10-km time trial performance and peak power. There was also significant improvement in relative peak power for both groups. The 10-km time trial performance and relative peak power showed a moderate inverse correlation.ConclusionThese findings showed that both intermittent sprint and plyometric training resulted in improved 10-km running performance despite reduction in training mileage. The improvement in running performance was accompanied by an improvement in peak power and showed an inverse relationship with relative peak power.     

Rebuttal

Abstract

The problem of the study was to investigate the relationship between maximum strength and muscular endurance; also the relationship between maximum strength and percentage of maximum strength held before and after an extended period of isometric training. The subjects (N = 60) were divided into two equal groups, control and experimental. The experimental group was further divided into two subgroups of high and low strength. The control group was tested for maximum strength and endurance once at the beginning of the experiment and once after 20 days. The subjects in the experimental group were tested for maximum strength and endurance before they embarked on a 20-day period of isometric training. They held tension for 100 sec. in the morning and again in the afternoon. Periodic tests were on the 5th, 10th, 15th, and 20th day. There was a significant relationship between maximum strength and endurance and a negative and generally significant relationship between maximum strength and percentage of maximum strength held.     

Effects of 8-week endurance and resistance training programmes on cardiovascular stress responses,life stress and coping

ABSTRACT

This study tested the effect of 8-week endurance and resistance training programmes on cardiovascular stress responses, life stress, and coping. Fifty-two untrained but healthy female students were randomised to an 8-week endurance training, an 8-week resistance training, or a wait list control group. Before and after the training intervention, we assessed the groups’ cardiorespiratory fitness (VO2max test), self-reported life stress, coping strategies and cardiovascular reactivity to and recovery from a standardised laboratory stressor. Both endurance and resistance training programmes caused physiological adaptation in terms of increased VO2max after the intervention. For stress and coping parameters, participants in the training groups improved cardiovascular recovery from stress and reported having less stress in their everyday life after the intervention than participants in the control group, while the two training groups did not differ from each other. We did not find any significant differences in heart rate reactivity and coping strategies between the study groups. These results partly support that exercise training has stress-reducing benefits regardless of the type of exercise. Both endurance and resistance exercise activities may be effectively used to improve stress regulation competence while having less impact on changing specific coping strategies.     

Effect of resistance training regimens on treadmill running and neuromuscular performance in recreational endurance runners

Abstract

The purpose of this study was to assess the effects of heavy resistance, explosive resistance, and muscle endurance training on neuromuscular, endurance, and high-intensity running performance in recreational endurance runners. Twenty-seven male runners were divided into one of three groups: heavy resistance, explosive resistance or muscle endurance training. After 6 weeks of preparatory training, the groups underwent an 8-week resistance training programme as a supplement to endurance training. Before and after the 8-week training period, maximal strength (one-repetition maximum), electromyographic activity of the leg extensors, countermovement jump height, maximal speed in the maximal anaerobic running test, maximal endurance performance, maximal oxygen uptake ([Vdot]O_2max), and running economy were assessed. Maximal strength improved in the heavy (P = 0.034, effect size ES = 0.38) and explosive resistance training groups (P = 0.003, ES = 0.67) with increases in leg muscle activation (heavy: P = 0.032, ES = 0.38; explosive: P = 0.002, ES = 0.77). Only the heavy resistance training group improved maximal running speed in the maximal anaerobic running test (P = 0.012, ES = 0.52) and jump height (P = 0.006, ES = 0.59). Maximal endurance running performance was improved in all groups (heavy: P = 0.005, ES = 0.56; explosive: P = 0.034, ES = 0.39; muscle endurance: P = 0.001, ES = 0.94), with small though not statistically significant improvements in [Vdot]O_2max (heavy: ES = 0.08; explosive: ES = 0.29; muscle endurance: ES = 0.65) and running economy (ES in all groups < 0.08). All three modes of strength training used concurrently with endurance training were effective in improving treadmill running endurance performance. However, both heavy and explosive strength training were beneficial in improving neuromuscular characteristics, and heavy resistance training in particular contributed to improvements in high-intensity running characteristics. Thus, endurance runners should include heavy resistance training in their training programmes to enhance endurance performance, such as improving sprinting ability at the end of a race.     

Maximal Oxygen Intake and its Relationship to Endurance Capacity on a Bicycle Ergometer

Abstract

The relationship between maximal oxygen intake (Max V0₂) and the capacity for endurance performance was investigated in a sample of 30 male university students. Each subject performed two work capacity tests on a bicycle ergometer from which continuous, minute-by-minute oxygen intake values, the amount of work performed (kilopond-meters), and the length of the ride (seconds) were obtained. In addition, lean body weight and percent body fat were measured in order to ascertain their importance in the above relationship. The results indicate a fairly high correlation (r = .84) between Max VO₂ (liters/min.) and endurance capacity, but this relationship was reduced considerably when Max VO₂ was expressed relative to body weight (r=.37) and lean body weight (r = .18). However, when the influence of body weight and lean body weight were held statistically constant, the correlations of endurance capacity with Max VO₂ (ml/kg per min.) and Max VO₂ (ml/LBW/ min.) increased to r=.78 and r = .64 respectively. Thus, it was concluded that there is a substantial relationship between endurance capacity and Max V0₂ which is essentially independent of the form in which Max VO₂ is reported providing the influence of body weight and lean body weight on both variables are taken into account.     

Moderate-domain pulmonary oxygen uptake kinetics and endurance running performance

Abstract

The aims of this study were to determine if the primary time constant (τ) for oxygen uptake ([Vdot]O₂) at the onset of moderate-intensity treadmill exercise is related to endurance running performance, and to establish if τ could be considered a determinant of endurance running performance. Thirty-six endurance trained male runners performed a series of laboratory tests, on separate days, to determine maximal oxygen uptake ([Vdot]O_2max), the ventilatory threshold (V_T) and running economy. In addition, runners completed six transitions from walking (4 km · h^?1) to moderate-intensity running (80% V_T) for the determination of the [Vdot]O₂ primary time constant and mean response time. During all tests, pulmonary gas-exchange was measured breath-by-breath. Endurance running performance was determined using a treadmill 5-km time-trial, after which runners were considered as combined performers (n=36) and, using a ranking system, high performers (n=10) and low performers (n=10). Relationships between τ and endurance running performance were quantified using correlation coefficients (r). Stepwise multiple regression was used to determine the primary predictor variables of endurance running performance in combined performers. Moderate correlations were observed between τ, mean response time and endurance running performance, but only for the combined performers (r=?0.55, P=0.001 and r=?0.50, P=0.002, respectively). The regression model for predicting 5-km performance did not include τ or mean response time. The velocity at [Vdot]O_2max was strongly correlated to endurance running performance in all groups (r=0.72 – 0.84, P < 0.01) and contributed substantially to the prediction of performance. In conclusion, the results suggest that despite their role in determining the oxygen deficit and having a moderate relationship with endurance running performance, neither τ nor mean response time is a primary determinant of endurance running performance.     

Cardiorespiratory Adaptations to Training at Specified Intensities

Abstract

Sixteen college men were randomly divided into three training groups and one control group in a study of selected cardiorespiratory adaptations to six weeks of training exercises eliciting either 120, 150, or 180 heart rates. Training consisted of walking on the motor driven treadmill for 10 min. a day, 3 days per week. Highly significant differences were found in the analysis of pre-post Balke treadmill test scores. The Åstrand-Ryhming nomogram prediction of aerobic capacity also showed highly significant changes due to training. Analysis of group differences revealed that the 180 training group's improvement was significantly different from all other groups in both tests. The 150 group was found to be significantly different from the 120 and control groups in the Balke test analysis. No changes were noted in resting pulse rate nor in the pulse rate—oxygen consumption relationship. However, there were small positive differences in the grade required to elicit the training heart rates. The study supports the hypothesis that intense activity is necessary to bring about the changes associated with cardiorespiratory endurance.     

Effects of Various Periods of Inactivity on Retention of Newly Acquired Levels of Muscular Endurance

Abstract

Male university students (N = 54) engaged in an 8-week training program with sessions held three times per week. Each session consisted of one “all-out” bout of right elbow flexion on an arm lever ergometer against a resistance of 11.03 lbs. at a work rate of 40 repetitions per minute. Following the training phase of the study, the subjects were randomly assigned to three experimental groups and ceased training for either 8, 10, or 12 weeks. At the conclusion of the inactivity period, each subject retrained until his peak performance of the training program had been equaled or exceeded. The analysis of data revealed that no difference existed among the groups: (a) at the beginning of the training program, (b) at the termination of the training program, (c) following the various inactivity periods, and (d) in the number of sessions needed to retrain to the peak performance attained during the training period. The within-group analysis indicated that each group had experienced: (a) significant muscular endurance development during the training period, (b) significant loss of endurance during the period of inactivity, and (c) significant retention of the newly acquired endurance over the inactivity period. Peak performance during the retraining phase was achieved in approximately one-fourth the number of training sessions initially required to attain the same level during the developmental phase.     

Relative Endurance of High- and Low-Strength Women

Abstract

The purpose of this study was to analyze the relative endurance ability of women in terms of muscle mass, static muscle strength, and critical occluding tension levels (COTL). Women physical education majors volunteered as subjects for this study (N = 56). The percentages of grip strength used for the relative endurance tests were 30%, 45%, 60%, and 75% with local circulation to the forearm muscles intact and artificially occluded by a pressure cuff. Analysis of the data revealed that there was no significant difference in the endurance times of high- and low-strength women. The relationship between grip strength and relative endurance time for each tension level was insignificant (r = ?.23 to ?.34). These findings were discussed in light of the relatively small differences in muscle mass and similarity in COTL of high- and low-strength women.     

Revisiting the Development of Time Sharing Using a Dual Motor Task Performance

Abstract

The purpose of the study was to investigate the effect of a 2-min. isometric exercise training program on force and fatigue in a skeletal muscle. The subjects (N=60) were divided into two equal groups, control and experimental. The control group was tested twice, once at the beginning of the experiment and again after 20 days. The subjects in the experimental group were tested before embarked on a 20-day period of isometric training. held the tension for 2 min. in the morning and again in the afternoon. Periodic tests were on the 5th, 10th, 15th, and 20th days. Large gains of initial strength were recorded on the 5th day. Isometric training continued beyond five days produced no significant gains in initial strength althoughe was a significant increase in isometric endurance. Isometric exercise continued longer than 15 days resulted in a significant decrease in initial strength and isometric endurance.     

Validation of Criterion-Referenced Standards for Tests of Arm and Shoulder Girdle Strength and Endurance

Abstract

The purpose of this study was to establish criterion-referenced standards for selected tests of arm and shoulder girdle strength and endurance for college females. Several popular tests of arm and shoulder girdle strength and endurance were administered to equal numbers of trained and untrained college females (N = 92) to generate data for the analysis. The contrasting groups method (Berk, 1976; Safrit & Wood, 1990) yielded the following criterion cutoff scores that classified college females as trained or untrained on the basis of regular upper arm and shoulder girdle resistance training: pull-ups = .5 repetitions (reps), 90° push-ups = 16 reps, flexed arm hang = 5s, seated chest press = 24.5 kg, seated biceps curl = 16.4 kg, seated lat pull (latissmus dorsi pull-down) = 38.2 kg, absolute strength index = 86.4 kg, and relative strength index = .6 kg per kg of body weight. Cross-validation of the standards on an independent sample of college females (N = 112) suggested stability of the cutoff scores for pull-ups, flexed arm hang, and relative strength.     

Index for Volume 56 (1985)

Abstract

This study was a staff experiment carried out in 1953 as a follow-up to several preliminary experiments by graduate students at the University of Illinois, School of Physical Education. The studies were carried out in the Physical Fitness Research Laboratory. The preliminary studies as well as the staff experiment of 1953 and the reversal experiment of 1954 all showed some advantage for supplementary feedings of wheat germ oil (WGO) administered during or immediately following physical conditioning periods of conditioning exercises and swimming in an indoor pool with water temperature 74°-76° F. The subjects were adult men, 26–60 years of age, mainly sedentary, volunteers from the nonphysical education staff.

The WGO capsules (20 capsules per day, 3 minims each, and each containing 175 mg. of WGO and 0.44 mg. of mixed tocopherol) were fed for eight weeks in connection with the progressive physical training experiment. Two groups of eight men each were matched in treadmill-running time, the brachial pulse wave and age. Two other inactive control groups of 5 men each were tested at the beginning (T₁) and at the end (T₂) of the eight week period. The group results show significant advantage for the experimental subjects who took WGO over those who did not in both performance (willpower dominated) tests and in naive (non-willpower) tests.

The physiological advantage is shown in terms of running endurance in “all-out” treadmill runs, T-wave of the ECG (CR_iv-vlead), lower systolic blood pressure, the Schneider Index and the Illinois total body reaction-time test in response to light, sound, and combined signals. Individual differences in response are shown and some of the factors which cause such variations are identified.     

Effects of different types of exercise on muscle mass,strength, function and well-being in elderly

Abstract

Poor muscle strength and physical function have been associated with higher risk of hospitalisation and lower well-being among the elderly. Physical training increases muscle strength, endurance and physical function as well as psychological outcomes. Exercise among older adults is often used to improve these variables, but few have compared the effects of different types of training in parallel independent groups. Thus, the aim of the present study was to investigate the effect of three different types of training on body composition, muscle strength, physical function and well-being in the elderly. A total of 118 community-dwelling older adults (mean age 74.3, s=4.6 years, 68% women) completed a 13-week randomised controlled exercise-trial involving four groups: traditional strength training (STG), functional strength training (FTG), endurance training (ETG) and control (CON). Stair climb with load improved more in FTG than CON (P<0.05), and the two strength groups performed better in the functional upper body test (P<0.05). STG increased strength more than CON in all exercises (P<0.001), while FTG increased strength more than CON in the chest press, shoulder press and knee extension (P<0.05). Lean body mass (LBM) increased in all training groups, which differed significantly from CON (P<0.05). ETG decreased their fat mass compared to CON (P<0.001). The only significant effect on well-being indices was improved life satisfaction in FTG at week 5 (P<0.05). We also observed significant correlations between change in some of the functional tests and change in positive affect.

All three types of training can enhance physical capacity. Functional strength training can be a cost effective form of training in terms of less demand for instructors and equipment and could be an effective way to improve physical function, strength and indices of well-being in the elderly.     

Coaction Effects on a Muscular Endurance Task

Abstract

The effect of one and three coactors on an individual's performance of a muscular endurance task was determined for 8-, 13-, and 18-year-old males. Subjects extended the dominant leg in a horizontal position for as long as possible under one of three conditions: alone, in pairs, and in groups of four. Results showed that individuals in quadrads performed significantly better than individuals in dyads and alone. No significant difference was found between individuals performing alone and in dyads. Eight-year-olds were found to be superior to the two older age groups, but the age factor was independent of the coaction effect.     

Left ventricular oxidant and antioxidant markers induced by lifestyle modification in rats exposed to lead acetate

Abstract

Responses of the left ventricle oxidant/antioxidant markers such as glutathione peroxidase (GPx), superoxide dismutase (SOD), malondialdehyde (MDA) and protein carbonyls (PCs) induced by lifestyle modification, including turmeric supplementation and exercise training, were investigated in rats during chronic exposure to lead acetate. Forty male rats were randomly divided into five groups: (1) lead acetate; (2) turmeric; (3) endurance training; (4) training + turmeric; and (5) sham-operated groups. Enzyme activities were determined in rat hearts after receiving 20 mg·kg^?1 of lead acetate (groups 1 to 4) and 30 mg·kg^?1 turmeric (groups 2 and 4) for 8 weeks, three times a week. In addition, the rats in groups 3 and 4 performed treadmill running at a speed of 15 to 22 m·min^?1 for 25 to 64 min, five times a week for 8 weeks. One way ANOVA analyses indicated that administration of lead evoked a significant increase in MDA and PC and significant decreases in GPx and SOD activity in the left ventricular homogenates. However, endurance training and\or turmeric supplementation resulted in a significant decrease in MDA and PC levels and significantly increased levels of GPx and SOD. These results suggest that lifestyle modification may have a cardioprotective effect by ameliorating lead-induced cardiotoxicity.