Water-based resistance training program with isolated concentric action improves physical functional capacity and muscular strength in older women

Background

Resistance training has proven to be an excellent method for counteracting aging physical dysfunctions. However, its application in the liquid environment is not yet fully elucidated.

Aim

To investigate the effects of water-based resistance training (WBRT) with the concentric phase performed as fast as possible, compared to conventional resistance training (CRT), on physical functional capacity, muscle strength, and body composition in older women.

Methods

Thirteen healthy older women participated in the WBRT and 11 in the CRT. Estimation statistics focused on the effect size of the experiment/intervention were used. We also analyzed the intervention effect based on the percentage delta between WBRT and CRT.

Results

The WBRT group showed a negative large effect (d?=?? 0.922; p?=?0.0274) for the timed up and go, and a large effect for chair rise in 30″ and the elbow flex test (d?=?1.58; p?=?0.0012; d?=?2.8; p?=?0.01) respectively. Intervention comparisons based on the delta percentage between WBRT and CRT presented an intermediate effect (d?=?0.606; p?=?0.157) for the stair climb, a large effect (d?=?0.988; p?=?0.0282) for the timed up and go, and a large negative effect [d?=?? 1.32 (90.0% CI ? 1.92, ? 0.646); p?=?0.0038] for the elbow flex test. Concentric extensor-flexor peak torque (60°/s) showed an intermediate effect (d?=?0.749; p?=?0.0876; d?=?0.65; p?=?0.122 respectively). Body fat (%) demonstrated an intermediate effect (d?=?0.523; p?=?0.234).

Conclusion

WBRT with the concentric phase performed as fast as possible was able to improve physical functional capacity and maximal knee extension strength of older women.

     

The effects of water-based strength exercise on quality of life in young women

Background

Exercise improves quality of life (QoL). However, little is known concerning the effects of different volumes of strength exercise on QoL. The aims of this study are to: (1) evaluate the effects of water-based strength exercise on QoL of healthy young women and (2) compare the effects of different volumes of water-based strength exercises on QoL of healthy young women.

Methods

Sixty-six participants were randomly allocated into four groups with different volumes of exercise. The participants performed water-based strength exercises for 20 weeks, two times a week, supervised by trained physiologists.

Results

A significant improvement was found in overall QoL (F = 5.96; p = 0.018) and in physical (F = 22.01; p < 0.001), psychological (F = 8.408; p = 0.006) and environment domains (F = 8.34; p = 0.006). In addition, a significant decrease of depressive symptoms was found (F = 22.32; p < 0.001). No difference was found between groups in any domain of QoL or depressive symptoms.

Conclusion

Water-based strength exercise improves specific domains of QoL and decreases depressive symptoms of young healthy women. Different volumes of exercise promote similar effects on QoL and depressive symptoms.

     

Resistance training in postmenopausal women with and without hormone therapy

PURPOSE: The main purpose of this study was to analyze the impact of a 1-yr resistance-training program on body composition and muscle strength in postmenopausal women, and to describe the impact of hormone replacement therapy (HRT) on body composition changes, with and without exercise. Secondarily, we wanted to study dose-response relationships between measures of program compliance and changes in primary outcomes. METHODS: Subjects were postmenopausal women (40-66 yr) randomly assigned to an exercise (EX) group (N = 117) and a nonexercise group (N = 116). The EX group participated in a 1 yr trainer-supervised resistance-training program, 60-75 min.d-1, 3 d.wk-1. Lean soft tissue (LST) and fat tissue (FT) changes were measured by dual-energy x-ray absorptiometry and strength by one-repetition maximum testing. RESULTS: Significant (P < 0.001) gains in LST were observed for women who exercised, regardless of HRT status, whereas women who did not exercise lost LST (P < 0.05) if they were not taking HRT, and gained LST (P = 0.08) if they were on HRT. The only significant FT losses were observed for women who exercised while on HRT (P < 0.05). Strength increases were observed at all sites (P < 0.001). Total weight lifted by subjects in their training sessions was a significant predictor of changes in LST (P < 0.001) and strength (P < 0.01). CONCLUSIONS: Resistance and weight-bearing exercise significantly changed total and regional body composition in postmenopausal women by increasing LST in all women and decreasing FT in women on HRT. Hormone therapy showed no independent effects on body composition, but it protected nonexercising women from losses in LST. The lean and muscle strength changes observed were partially dependent on the volume of training, as expressed by attendance and total weight lifted in 1 yr of training.     

Muscular strength and bone density with weight training in middle-aged women

Previous research has demonstrated positive correlations between bone mass and both physical activity and muscular strength. There is a paucity of information describing the specific type of exercise which most benefits the human skeleton. The effects of a 1 yr weight training program on 18 middle-aged women participating in an endurance dance program (E + W) compared with 17 other women in the endurance dance program only (E) and with 19 sedentary controls (C) were studied by measuring muscular strength and bone mineral density (BMD). Eighteen women in the E + W group demonstrated increases in all strength measurements, whereas the E and C groups either had smaller increases or had declined. A significant group x test interaction term, indicating that groups responded differently over time, was observed for nondominant isokinetic elbow flexion measured through the range of motion at a constant velocity of 60 degrees.s-1 (P less than 0.05), nondominant isokinetic elbow extension at 180 degrees.s-1 (P less than 0.01), and nondominant isokinetic elbow flexion at 180 degrees.s-1 (P less than 0.05). BMD did not change significantly except that a significant group x test interaction term appeared for the radius ultradistal site (P less than 0.01). BMD of the humerus and femoral Ward's triangle increased nonsignificantly in both E and E + W over the year. This weight training program increased muscular strength but did not increase measured bone mass.     

The effects of strength training in patients with selected neuromuscular disorders

Five subjects with spinal muscular atrophy, limb-girdle or facioscapulohumeral muscular dystrophy, were studied. Measurements pre- and post-training included: maximum isometric, dynamic and isokinetic strength, in single-arm curl and double-leg press exercises; contractile properties of the elbow flexors; computerized tomography of the upper arms and thighs; muscle biopsies from the biceps brachii muscle of each arm in three subjects. Dynamic weight training was performed 3 times per week for 9 wk; exercises comprised unilateral arm curls (the contralateral arm acted as a control), and bilateral leg press. Strength increases in the trained arm were between 19 and 34%, and from -14 to +25% in the control arm; leg strength increased from 11 to 50%. Moreover, the pretraining maximum load could be lifted from 3 to 48 times in the trained limbs, and from 1 to 13 times in an untrained limb before fatigue. Contractile properties of the elbow flexors were unchanged with training, but pre-intervention, three subjects demonstrated incomplete motor unit activation. Most of the gains in strength were apparently due to a neural adaptation, rather than muscle hypertrophy. The tomograms and biopsy samples were inadequate to determine muscle, or muscle fiber areas with confidence; they did indicate however, no additional overt muscle structural damage. Strength training may be a potentially useful therapeutic option in the management of selected neuromuscular disorders.     

Resistance training improves insulin signaling and action in skeletal muscle

Resistance training can improve glucose transport in both normal and insulin-resistant skeletal muscle by enhancing the activation of the insulin signaling cascade and increasing GLUT-4 protein concentration. These training-induced alterations improve the quality of the skeletal muscle and can occur independent of significant increases in skeletal muscle mass.     

Concurrent strength and endurance training improves physical capacity in patients with peripheral arterial disease

Peripheral arterial disease (PAD) patients suffer from reduced blood flow to the lower extremities, which causes impaired walking ability. Plantar flexion (PF) endurance training and maximal strength training (MST) induce distinct types of improvements in walking ability in PAD. However, the combined effects of both exercises are still not explored in these patients. This study examined whether concurrent MST and PF training would induce similar training responses as each training mode alone. Ten patients with PAD underwent 8 weeks of concurrent leg press MST and PF training, three times a week. The reference group (n=10) received recommended exercise guidelines. The training group improved treadmill peak oxygen consumption and incremental protocol time to exhaustion with 12.7 ± 7.7% and 12.6 ± 13.2%. Leg press maximal strength and rate of force development improved with 38.3 ± 3.1% and 140.1 ± 40.3%, respectively, along with a 5.2 ± 6.2% within group work economy improvement. No changes appeared in the reference group. Compared with previous studies, concurrent MST and PF training appear to induce similar training responses in PAD patients as when each training mode is executed alone, and without any adverse effects.     

Low-intensity exercise improves quality of life in patients with Crohn's disease.

OBJECTIVE: This study examines the effects of a low-intensity walking program on the quality of life in patients with Crohn's disease. DESIGN: Patients were randomized into exercise and nonexercise groups for a prospective study. SETTING: Patients were recruited at the inflammatory bowel disease outpatient clinic at the London Health Science Center, London, Ontario. PATIENTS: Thirty-two adult patients met the inclusion criteria of (1) mildly active disease or disease in remission, (2) habitual physical activity of less than 2 times per week of vigorous activity, (3) not anticipating change of dose or type of medication for Crohn's disease, and (4) no history of cardiovascular disease. All 32 patients who entered the study completed the 3-month study. INTERVENTION: Patients performed low-intensity walking at an interval of 3 times per week for a duration of 3 months. Each walking session lasted for 30 minutes. MAIN OUTCOME MEASUREMENTS: The Inflammatory Bowel Disease Questionnaire, the Inflammatory Bowel Disease Stress Index, and the Harvey-Bradshaw Simple Index were used as outcome. Survey measurements were recorded at 1-month intervals on commencement of the walking program. RESULTS: Patients in the exercise group experienced a statistically significant (P < 0.05) improvement in quality of life in all 3 of the outcome measurement questionnaires with no detrimental effects in terms of disease activity. CONCLUSION: A low-intensity walking program may have a beneficial effect in patients with Crohn's disease and improve their quality of life with no exacerbations in disease symptoms.     

Effect of 8 months of whole-body vibration training on quality of life in elderly women

Whole-body vibration (WBV) training in elderly may improve muscle strength, muscle power and postural control. However, knowledge about the effect of WBV training in elderly on measures of health as a multidimensional construct (health-related quality of life, HRQoL) is scarce. The present study aimed to determine the effects of WBV training on HRQoL in elderly women. A total of 37 women (aged 82.4 ± 5.7 years) were recruited and were assigned to either the WBV group or to the control (CON) group. After 8 months of training, the WBV group showed non-significant changes on HRQoL and additional health-related outcomes (fall risk, life satisfaction or cognitive status). Our findings are in disagreement with previous studies of shorter duration (6 weeks), which reported positive significant changes in HRQoL in elderly people. Discrepancies among studies may be partly attributed to methodological differences, but the existence of publication bias in previous studies cannot be discarded.     

Recreational soccer training improves heart-rate variability indices and physical performance in untrained healthy adolescent

The aim of this study was to evaluate the effects of soccer training on short-term heart-rate variability, blood pressure, and physical fitness in untrained healthy adolescents. Twenty-two adolescent boys took part in this study: 11 boys were randomly assigned to participate in an 8-week soccer training and 11 boys served as a control group. Soccer exhibited significant increases in high-frequency power (difference 52.9%, P = 0.03, effect size: ES = 1.2), root mean squared of the standard deviation rMSSD (10.8%, P = 0.02, ES = 1), and a significant decrease in sympathetic activity LF (26.3%, P = 0.004, ES = 1.4). The control group showed an increase in rMSSD (9.4%, P = 0.05, ES = 1). The soccer group showed increases in estimated aerobic fitness (30.9%, P = 0.001, ES = 1.50) and 20-m sprint performance (4.1%, P = 0.004, ES = 0.8) with a trend to an improvement in horizontal jumping (3.8%, P = 0.15, ES = 0.8). In conclusion, soccer-based training improved measures of both physical fitness and autonomic function making soccer an effective training strategy for improving health-related fitness measures in untrained adolescents.     

Whole-body vibration training improves flexibility,strength profile of knee flexors,and hamstrings-to-quadriceps strength ratio in females

ObjectivesShort-term whole-body vibration training (WBVT) has emerged as an exercise method for improving neuromuscular performance and has been proposed for injury prevention and rehabilitation. This study investigated the effects of a short-term (≤2 months) WBVT program using a side-to-side vibration on: (i) strength profile of knee extensors (KE) and flexors (KF), (ii) “functional” hamstrings-to-quadriceps ratio (ECC_KF/CON_KE), (iii) flexibility and (iv) vertical jumping performance (VJ). Furthermore, we explored the retention of performance gains 21 days following WBVT.DesignRandomized-controlled trial.MethodsTwenty-six moderately active females (20.40 ± 0.27 years) were assigned to a vibration (VG) or a control group (CG). The short-term WBVT program consisted of sixteen-sessions on a side-to-side vibration platform (frequency: 25 Hz, amplitude: 6 mm, 2 sets × 5 min). Isokinetic and isometric peak torque of KE and KF, ECC_KF/CON_KE, flexibility, and VJ were measured pre, 2 days post, and 21 days following the cessation of WBVT.ResultsPost-training values of flexibility, isokinetic and isometric peak torques of KF and ECC_KF/CON_KE ratio were higher than pre-training values in VG (p < 0.05); however, they remained unchanged in CG. Post-training values were greater in VG vs. CG (p < 0.05). Twenty-one days following WBVT, post-training values were no longer significantly different than pre-training values. The short-term WBVT program had no effect on strength profile of KE and on VJ.ConclusionsA short-term side-to-side WBVT program improved flexibility, the strength profile of knee flexors, and the “functional” hamstrings-to-quadriceps ratio in moderately active females. Coaches and clinical practitioners should consider this type of training as an effective exercise mode for improving the strength asymmetry of reciprocal muscles at the knee joint.     

Visual feedback training improves postural adjustments associated with moving obstacle avoidance in elderly women

The study examined the impact of visually guided weight shifting (WS) practice on the postural adjustments evoked by elderly women when avoiding collision with a moving obstacle while standing. Fifty-six healthy elderly women (70.9+/-5.7 years, 87.5+/-9.6 kg) were randomly assigned into one of three groups: a group that completed 12 sessions (25 min, 3s/week) of WS practice in the Anterior/Posterior direction (A/P group, n=20), a group that performed the same practice in the medio/lateral direction (M/L group, n=20) and a control group (n=16). Pre- and post-training, participants were tested in a moving obstacle avoidance task. As a result of practice, postural response onset shifted closer to the time of collision with the obstacle. Side-to-side WS resulted in a reduction of the M/L sway amplitude and an increase of the trunk's velocity during avoidance. It is concluded that visually guided WS practice enhances elderly's ability for on-line visuo-motor processing when avoiding collision eliminating reliance on anticipatory scaling. Specifying the direction of WS seems to be critical for optimizing the transfer of training adaptations.     

Resistance training and intra-abdominal adipose tissue in older men and women

PURPOSE: Little is known concerning the effects of resistance-exercise training (RT) on older adult's intra-abdominal adipose tissue (IAAT). The purpose of this study was to determine the effects of RT on fat distribution in 12 women and 14 men, aged 61-77 yr. METHODS: Computed tomography IAAT and abdominal subcutaneous adipose tissue (SAT), densitometry-determined body composition, one-repetition maximum (1-RM), and isometric strength were measured before and after 25 wk of RT. Training consisted of two sets of 10 repetitions at 65-80% of 1-RM, three times each week. RESULTS: There were similar increases in strength for both the men and women. Women improved 22% and 38% in the isometric strength test and 1-RM test, respectively, whereas the men improved 21% and 36%, respectively. A significant increase in fat-free mass (FFM) was found for both men and women. However, there was a significant gender x time interaction, which indicated that men increased FFM more than women (2.8 kg vs 1.0 kg, respectively). Similar decreases in fat mass (FM) were found for the men (1.8 kg) and women (1.7 kg). However, women lost a significant amount of IAAT (131 to 116 cm2), whereas the men did not (143 to 152 cm2). Similarly, women also lost a significant amount of SAT (254 to 239 cm2), but men did not (165 to 165 cm2). CONCLUSION: Despite similar decreases in FM after a 25-wk RT program, older women lost significant amounts of IAAT and SAT, whereas the older men did not.     

飞行人员躯体疼痛与相关病症的情况调查

目的：了解飞行人员躯体疼痛与相关病症的情况。方法通过对空军飞行人员问卷调查，了解军事飞行人员颈、肩、腰、背、腿痛与新发肌肉骨骼系统疾病情况，以及有关缓解措施。结果腰痛患病率最高（38.7%），腿痛患病率最低（15.6％）；1年内新发腰肌劳损的发病率最高（28.7%），背肌劳损的发病率最低（8.1%），且发病情况呈现明显的机种特点。引发躯体不同部位疼痛的主要因素为飞行加速度（G）值、头盔重量、飞行日留空时间、座舱座椅舒适度及体育锻炼损伤等；改进人机工效设计、加强肌肉锻炼，以及理疗、按摩等措施可有效预防和缓解疼痛不适。结论军事飞行人员躯体疼痛的患病率因部位不同而异，且呈明显机种特点，应采取综合保障措施进行有效防治。