Effects of a 6-month exercise program pilot study on walking economy, peak physiological characteristics, and walking performance in patients with peripheral arterial disease

The purpose of this study was to examine the effects of a 6-month exercise program on submaximal walking economy in individuals with peripheral arterial disease and intermittent claudication (PAD-IC). Participants (n = 16) were randomly allocated to either a control PAD-IC group (CPAD-IC, n = 6) which received standard medical therapy, or a treatment PAD-IC group (TPAD-IC; n = 10) which took part in a supervised exercise program. During a graded treadmill test, physiological responses, including oxygen consumption, were assessed to calculate walking economy during submaximal and maximal walking performance. Differences between groups at baseline and post-intervention were analyzed via Kruskal–Wallis tests. At baseline, CPAD-IC and TPAD-IC groups demonstrated similar walking performance and physiological responses. Postintervention, TPAD-IC patients demonstrated significantly lower oxygen consumption during the graded exercise test, and greater maximal walking performance compared to CPAD-IC. These preliminary results indicate that 6 months of regular exercise improves both submaximal walking economy and maximal walking performance, without significant changes in maximal walking economy. Enhanced walking economy may contribute to physiological efficiency, which in turn may improve walking performance as demonstrated by PAD-IC patients following regular exercise programs

Exercise self-efficacy of postmenopausal women resident in the tropics

Objectives: Weight gain and the associated increased risk of coronary artery disease are associated with the postmenopausal period. However, moderate intensity physical activity may be cardioprotective in this period. Australian women remain predominately sedentary despite the health benefits of regular exercise. Self-efficacy is an important predictor of exercise behaviour influencing exercise adoption when faced with potential barriers. Determination of exercise self-efficacy levels and the most significant barriers to exercise is necessary for the success of intervention programs for this population.\ud \ud Methods: Postmenopausal women (N=101) resident in tropical North Queensland were recruited via announcements in local media, service club newsletters and electronic bulletin boards. Following data collection, participants were categorised as exercisers (n=53) or non-exercisers (n=48) based on whether they had performed a minimum of 150min of accumulated moderate intensity exercise in the past 7 days. Exercise self-efficacy was determined via questionnaire.\ud \ud Results: Results indicated that exercisers had a higher level of exercise self-efficacy and felt significantly more confident to exercise when faced with barriers compared to non-exercisers (p<.001). Discriminant function analysis found that exercise self-efficacy provided the greatest discrimination between exercisers and non-exercisers. The barrier items of conflicting schedules, difficulty getting to an exercise location and the weather were the main contributors to discrimination between exercisers and non-exercisers.\ud \ud Conclusions: Findings suggest that future intervention programs should aim to increase exercise self-efficacy and address these barriers so that more postmenopausal women resident in North Queensland can obtain the health benefits of exercise

Psychological outcomes of physical activity : a theoretical perspective

Revue de synthèse des recherches concernant les mécanismes psycho-physiologiques des bienfaits psychologiques de l'activité physique incluant les effets sur l'affectivité et la fonction cognitiv

Effect of shoulder angle on physiological responses during incremental peak arm crank ergometry

This study examined the effect of shoulder angle and gender on physiological and perceptual responses during incremental peak arm ergometry. Healthy adults (nine males, seven females) volunteered for the study and completed an incremental arm ergometry test on two separate occasions at two different shoulder angles (90 degrees and 45 degrees). Initial work rate was set at 16 W x min-1 and was increased progressively until exhaustion. Cardiorespiratory and perceptual responses were recorded at the end of each minute and compared using separate three-way (position x work rate x gender) repeated-measures analyses of variance. The systematic bias of peak responses was examined using separate two-way (position x gender) analyses of variance, while reproducibility of these parameters was explored using intraclass correlation coefficients, measurement bias/ratio, and 95% ratio limits of agreement. Despite a significantly greater peak heart rate for the 45 degrees position, cardiorespiratory and perceptual responses were similar at peak exercise for both positions. Peak values for all variables, although similar, demonstrated similar and large inter-test variability for men and women. Reduction of the shoulder joint angle to 45 degrees did not enhance peak work rate and peak oxygen consumption during seated upper body exercise. Due to the large inter-test variability, arm ergometry should be conducted using the same seated position

The importance of movement specificity in isokinetic assessment

On recherche si le fait de modifier un test isocinétique pour le rendre plus spécifique à la performance dynamique améliore la relation entre le test et la performance et si le test spécifique est capable de mieux contrôler les modifications dues à l'entraînemen

Barrier-specific exercise self-efficacy in postmenopausal women resident in the tropics

Weight gain and the associated increased risk of coronary artery disease are associated with the postmenopausal\ud period. However, moderate intensity physical activity may be cardioprotective in this period. Australian women remain predominately sedentary however, despite the health benefits of regular exercise. Self-efficacy is an important predictor of exercise behaviour influencing exercise adoption when faced with potential barriers including age, health status, socio-economic status, geographical considerations and social and physical environments. Determination of the most significant barriers to exercise is necessary for successful intervention programs for the postmenopausal population. Postmenopausal women (N=87) resident in tropical north Queensland were recruited via announcements in local media, service club newsletters and electronic bulletin boards. Following data collection, participants were categorised as exercisers (n=55) or non-exercisers (n=32) based on whether they had performed a minimum of 150 minutes of accumulated moderate intensity exercise in the past 7 days. Exercise self-efficacy was determined via questionnaire. Discriminant function analysis\ud indicated that exercisers had a higher level of exercise self-efficacy (p < .00 I) and feel significantly more\ud confident to exercise when faced with barriers compared to non-exercisers. Of these barriers, conflicting schedules and feeling self-conscious were the main contributors to discrimination between exercisers and nonexercisers.\ud Seventy four percent of the total sample and 73% and 78% of the exercisers and non-exercisers were correctly classified respectively. Findings suggest that future intervention programs should aim to reduce these barriers so that more postmenopausal women resident in North Queensland can obtain the health benefits of exercise

Kinematic responses to plyometric exercises conducted on compliant and noncompliant surfaces

Jumping is an important performance component of many sporting activities. A number of training modalities have been used to enhance jumping performance including plyometrics. The positive effects of plyometric training on jumping performance are a function of the stretch-shortening cycle phenomenon. However, there has been little research on the effects of the surface on jumping performance. This study examined the effects of performing 2 different plyometric exercises, depth jump (DJ) and counter movement jump (CMJ), on noncompliant (ground) and compliant (mini-trampoline) surfaces. Male participants (N = 20; age = 21.8 +/- 3.8 years; height = 184.6 +/- 7.6 cm; mass = 83.6 +/- 8.2 kg) randomly performed 10 CMJ and 10 DJ on compliant and noncompliant surfaces. Kinematic data were determined via 2-dimensional high-speed video. There were significant (p < 0.05) differences in DJ and CMJ joint and segment range of movement for ankle, knee, hip and trunk, indicating less crouch when the participants performed plyometric exercises on the compliant surface

The effects of resisted sprint training on acceleration performance and kinematics in soccer, rugby union, and Australian football players

Acceleration is a significant feature of game-deciding situations in the various codes of football. However little is known about the acceleration characteristics of football players, the effects of acceleration training, or the effectiveness of different training modalities. This study examined the effects of resisted sprint (RS) training (weighted sled towing) on acceleration performance (0-15 m), leg power (countermovement jump [CMJ], 5-bound test [5BT], and 50-cm drop jump [50DJ]), gait (foot contact time, stride length, stride frequency, step length, and flight time), and joint (shoulder, elbow, hip, and knee) kinematics in men (N = 30) currently playing soccer, rugby union, or Australian football. Gait and kinematic measurements were derived from the first and second strides of an acceleration effort. Participants were randomly assigned to 1 of 3 treatment conditions: (a) 8-week sprint training of two 1-h sessions[middle dot]wk-1 plus RS training (RS group, n = 10), (b) 8-week nonresisted sprint training program of two 1-h sessions[middle dot]wk-1 (NRS group, n = 10), or (c) control (n = 10). The results indicated that an 8-week RS training program (a) significantly improves acceleration and leg power (CMJ and 5BT) performance but is no more effective than an 8-week NRS training program, (b) significantly improves reactive strength (50DJ), and (c) has minimal impact on gait and upper- and lower-body kinematics during acceleration performance compared to an 8-week NRS training program. These findings suggest that RS training will not adversely affect acceleration kinematics and gait. Although apparently no more effective than NRS training, this training modality provides an overload stimulus to acceleration mechanics and recruitment of the hip and knee extensors, resulting in greater application of horizontal power

Attentional style characteristics of injured professional rugby league players

Injury is of high prevalence in rugby league and has negative physical and psychological consequences for the players that experience them (National Health and Medical Research Council, 1994). Rugby league requires players to execute a range of skills including kicking, jumping, passing, catching, and tackling. These skills require a\ud combination of speed, agility, strength, anaerobic and aerobic power. Played by a large number of Australian male athletes, around 30% of injuries incurred playing rugby league are classified as major (Gabbett, 2001). It is generally considered that insufficient information is\ud available on football injuries and that professional athletes should be considered separately to the general population. Psychological research of injury in rugby league is limited and psychological characteristics measured in prospective studies of rugby league injury have not previously been considered

Effect of exercise mode on heart rate variability during steady state exercise

This study examined the effect of exercise mode on geometrical, and time and frequency domain measures of heart rate variability (HRV) during steadystate, moderate intensity exercise of the same HR. Seventeen healthy, active male participants volunteered for this study and completed a treadmill VO2max determination. One week later, cardiorespiratory, perceptual and HRV measures were recorded during seated rest (15 min) and consecutive bouts (15 min) of steady-state exercise at 50 and 65% of maximal HR. Exercise was performed using either upper body (arm ergometer), lower body (cycle) or whole body (treadmill) modes. Separated by 1 week and in a random order, participants undertook the same procedures with the remaining exercise modes. Cardiorespiratory, perceptual and HRV responses were determined during rest and steady-state exercise and analysed by twoway (mode vs. stage) repeated measures ANOVA and post hoc pairwise comparisons. Apart from a reduced respiratory rate during lower body exercise, whole and lower body exercise resulted in similar cardiorespiratory, perceptual and HRV responses. Compared to whole or lower body exercise, upper body exercise resulted in significantly (P\0.05) greater measures of HRV particularly those within the very low (0–0.04 Hz) and low (0.04–0.15 Hz) frequency bands, greater rating of perceived exertion and less oxygen consumption. Upper body, moderate intensity exercise resulted in greater HRV compared to whole or lower body exercise with further studies necessary to elucidate the mechanisms and clinical implications for this greater HRV