Virtual reality-based training improves community ambulation in individuals with stroke: a randomized controlled trial

This is a single blind randomized controlled trial to examine the effect of virtual reality-based training on the community ambulation in individuals with stroke. Twenty subjects with stroke were assigned randomly to either the control group (n=9) or the experimental group (n=11). Subjects in the control group received the treadmill training. Subjects in the experimental group underwent the virtual reality-based treadmill training. Walking speed, community walking time, walking ability questionnaire (WAQ), and activities-specific balance confidence (ABC) scale were evaluated. Subjects in the experimental group improved significantly in walking speed, community walking time, and WAQ score at posttraining and 1-month follow-up periods. Their ABC score also significantly increased at posttraining but did not maintain at follow-up period. Regarding the between-group comparisons, the experimental group improved significantly more than control group in walking speed (P=0.03) and community walking time (P=0.04) at posttraining period and in WAQ score (P=0.03) at follow-up period. Our results support the perceived benefits of gait training programs that incorporate virtual reality to augment the community ambulation of individuals with stroke.     

Carbohydrate supplementation and exercise performance at high altitude: a randomized controlled trial

Acute carbohydrate supplementation decreases effort perception and increases endurance exercise capacity at sea level. It also improves laboratory-based endurance performance at altitude. However, the effect of chronic carbohydrate supplementation at altitude, when acclimatization may attenuate carbohydrate effects, achieved doses are lower and metabolic effects may be different, is unknown and was therefore focused on in the present study. Forty-one members of a 22-day high altitude expedition were randomized in a double-blind design to receive either placebo or carbohydrate supplementation. Diet was manipulated with commercially available energy drinks consumed ad libitum throughout the expedition. Participants performed a mountaineering time trial at 5192?m, completed submaximal incremental exercise step tests to assess cardiovascular parameters before, during, and after the expedition, and recorded spontaneous physical activity by accelerometer on rest days. Compared to placebo, compliant individuals of the carbohydrate-supplemented group received daily an additional 3.5±1.4?g carbohydrate·kg body mass(-1). Compliant individuals of the carbohydrate supplemented group reported 18% lower ratings of perceived exertion during the time trial at altitude, and completed it 17% faster than the placebo group (both p<0.05 by t-test). However, cardiovascular parameters obtained during submaximal exercise and spontaneous physical activity on rest days were similar between the two groups (all p>0.05 by analysis of variance). This study utilized testing protocols of specific relevance to high altitude sojourners, including the highest mountaineering time trial completed to date at altitude. Chronic carbohydrate supplementation reduced ratings of perceived exertion and improved physical performance, especially during prolonged and higher intensity exercise tasks.     

Effects of whole body vibration training on postural control in older individuals: a 1 year randomized controlled trial

This randomized controlled trial investigated the effects of a 12 month whole body vibration training program on postural control in healthy older adults. Two hundred and twenty people were randomly assigned to a whole body vibration group (n=94), a fitness group (n=60) or a control group (n=66). The whole body vibration and fitness groups trained three times a week for 1 year. The vibration group performed exercises on a vibration platform and the fitness group performed cardiovascular, strength, balance and stretching exercises. Balance was measured using dynamic computerized posturography at baseline and after 6 and 12 months. Whole body vibration training was associated with reduced falls frequency on a moving platform when vision was disturbed and improvements in the response to toes down rotations at the ankle induced by the moving platform. The fitness group showed reduced falls frequency on the moving surface when vision was disturbed. Thus, whole body vibration training may improve some aspects of postural control in community dwelling older individuals.     

Effects of functional exercise training on performance and muscle strength after meniscectomy: a randomized trial

Muscular deficits and functional limitations have been found years after meniscectomy of the knee. The purpose of this randomized controlled trial was to examine the effect of functional exercise training on functional performance and isokinetic thigh muscle strength in middle-aged patients subsequent to meniscectomy for a degenerative tear. Four years after meniscectomy, 45 patients (29 men, 16 women) were randomized to functional exercise training, supervised by a physical therapist, three times weekly for 4 months or to no intervention. The exercise program comprised of postural stability training and functional strength and endurance exercises for leg and trunk muscles. Outcomes were three functional performance tests and isokinetic muscle strength. Thirty patients (16 exercisers/14 controls) completed the study. Compared with control patients, the exercise group showed significant improvement in one-leg hop (change 8 vs 2 cm; P =0.040), hamstrings strength 60°/s ( P =0.033), and quadriceps endurance 180°/s ( P =0.001). Functional exercise training was well tolerated and improved functional performance and thigh muscle strength in this group of middle-aged subjects with a previous degenerative meniscal injury and partial meniscectomy.     

Aerobic exercise and the lipid profile in type 1 diabetic men: a randomized controlled trial

PURPOSE: Despite the potential importance of favorable changes in the lipid profile produced by aerobic exercise, training-induced lipid profile changes in atherosclerosis-prone type 1 diabetes mellitus (DM) have not heretofore been adequately addressed. METHODS: We assessed the effect of a 12- to 16-wk aerobic exercise program on cardiorespiratory fitness and the lipid profile in young men with type 1 DM. Generally active men aged 20-40 yr with type 1 DM (N = 56) were randomized into training (N = 28) and control (untrained, N = 28) groups after baseline measurements. Training consisted of 30-60 min moderate-intensity running 3-5 times a week for 12-16 wk. RESULTS: For the 42 men finishing the study, peak oxygen consumption (VO2 peak) increased significantly only in the trained group. Total and low-density lipoprotein (LDL) cholesterol and apolipoprotein (apo) B decreased and the high-density lipoprotein (HDL)/apo A-I ratio increased in the trained group. HDL and apo A-I increased in both groups. The exercise program brought about improvements in the HDL/LDL and apo A-I/apo B ratios and apo B and triglyceride levels when comparing the relative (%) changes in the trained versus control group. In the trained group, men with HDL/LDL ratios below the group median at baseline showed even more favorable changes in their lipid profile than those with higher initial HDL/LDL ratios. Body mass index, percent body fat and hemoglobin A1c did not change during the training period in either group. CONCLUSIONS: Endurance training improved the lipid profile in already physically active type 1 diabetic men, independently of effects on body composition or glycemic control. The most favorable changes were in patients with low baseline HDL/LDL ratios, likely the group with the greatest benefit to be gained by such changes.     

Effects of different exercise training programs on body composition: A randomized control trial

We aimed to investigate the effects of different exercise training programs on body composition parameters in sedentary middle‐aged adults. A total of 89 middle‐aged adults (53.5 ± 4.9 years old; ~53% women) participated in the FIT‐AGEING study. A 12‐week randomized controlled trial was performed with a parallel group design. The participants were randomly assigned to (a) a concurrent training based on physical activity recommendation from the World Health Organization group (PAR group), (b) a high‐intensity interval training group (HIIT group), and (c) a high‐intensity interval training group adding whole‐body electromyostimulation group (WB‐EMS group). A significant decrease of fat body mass, fat body mass index, and visceral adipose tissue was observed in all training modalities compared to the control group (all P ≤ 0.001). There was a significant increase in lean body mass in the HIIT group as well as in the WB‐EMS group compared to the control group and the PAR group (all P ≤ 0.044), whereas an increment of lean body mass index was only observed in the WB‐EMS group compared to the control group and the PAR group (all P ≤ 0.042). A significant increase of bone mineral content was observed in the WB‐EMS group compared to the control group (P = 0.015), while no changes were found in the PAR group and in the HIIT group compared to the control group (all P ≥ 0.2). Our findings suggest that PAR, HIIT, and WB‐EMS can be used as a strategy to improve body composition parameters, obtaining slightly better results with the application of WB‐EMS.     

Effects of exercise training on men seropositive for the human immunodeficiency virus-1.

We examined the effects of chronic exercise on fitness and immune status in Caucasian males (34.9 +/- 5.6 yr) diagnosed by Western blot as seropositive for the HIV-1 virus. The exercise regimen involved 12 wk of 1 h sessions 3 d.wk: 20 min of cycle exercise at 60-80% HRreserve was followed by 35 min of strength and flexibility training. After matching subjects on health status (modified Walter Reed criteria), subjects (N = 37) were randomly assigned to exercise or a counseling control condition. Changes in strength, responses to the YMCA cycle test, and serum lymphocytes were tested by MANOVA in a condition (exercise or counseling)-by-time (pretest, posttest) design with repeated measures on time. Results indicated significant (P less than 0.001) group-by-time interactions for strength (N.m) (chest press and leg extension) and for HR (beats.min-1) and total time (TT) on the cycle test at 150 W. Strength and TT increased and HR decreased in the exercise condition, while control subjects did not change. Total leukocyte, lymphocyte, CD4+, and CD8+ cell counts, and the CD4+/CD8+ ratio were statistically unchanged for each condition. We conclude that HIV-1+ men, including those symptomatic for AIDS-related complex, can experience significant increases in neuromuscular strength and cardiorespiratory fitness without changes in lymphocyte phenotypes or clinical diagnosis when the exercise regimen is prescribed and monitored in accordance with ACSM guidelines for healthy adults.     

Effects of inspiratory muscle training on exercise capacity and spontaneous physical activity in elderly subjects: a randomized controlled pilot trial

Inspiratory muscle training (IMT) has been shown to improve exercise capacity in diseased populations. We chose to examine the effects of eight weeks of IMT on exercise capacity and spontaneous physical activity in elderly individuals. Eighteen moderately active elderly subjects (68.1 +/- 6.8 years [mean +/- SD]; range 58 - 78 years) were randomly assigned to either an experimental group (n = 9) or a control group (n = 9) in a double-blind manner. All subjects underwent inspiratory muscle testing, treadmill exercise testing and a four-day measurement period of spontaneous physical activity (using accelerometry) both pre- and post-intervention. The experimental group underwent eight weeks of incremental IMT using a pressure threshold device, while the control group underwent sham training using identical devices. After IMT training, inspiratory muscle strength (mean + 21.5 cm H (2)O; 95 % CI: 9.3, 33.7; p = 0.002), V.O (2peak) (+ 2.8 ml x min (-1) x kg (-1); 95 % CI: 0.5, 5.2; p = 0.022), time to exhaustion during a fixed workload treadmill test (+ 7.1 min; 95 % CI: 1.8, 2.4; p = 0.013) and time engaged in moderate-to-vigorous physical activity (+ 59 min; 95 % CI: 15, 78; p = 0.008) improved. Except for a decline in moderate-to-vigorous physical activity, no significant changes were seen in the control group. Therefore, IMT may be a useful technique for positively influencing exercise capacity and physical activity in elderly individuals.     

Similar magnitude of post‐exercise hyperglycemia despite manipulating resistance exercise intensity in type 1 diabetes individuals

The aim of this study was to compare the glycemic and glucoregulatory hormone responses to low‐ and moderate‐intensity morning resistance exercise (RE) sessions in type 1 diabetes (T1DM). Following maximal strength assessments (1RM), eight T1DM (HbA_1C:72 ± 12 mmol/mol, age:34 ± 7 years, body mass index:25.7 ± 1.6 kg/m²) participants attended the research facility on two separate occasions, having fasted and taken their usual basal insulin but omitting rapid‐acting insulin. Participants performed six exercises for two sets of 20 repetitions at 30%1RM during one session [low‐intensity RE session (LOW)] and two sets of 10 repetitions at 60%1RM during another session [moderate‐intensity RE session (MOD)], followed by 65‐min recovery. Sessions were matched for total mass lifted (kg). Venous blood samples were taken before and after exercise. Data (mean ± SEM) were analyzed using analysis of variance (P ≤ 0.05). There were no hypoglycemic occurrences throughout the study. Blood glucose rose similarly between sessions during exercise (P = 0.382), remaining comparable between sessions throughout recovery (P > 0.05). There was no effect of RE intensity on metabolic acidosis (P > 0.05) or peak growth hormone responses (P = 0.644), but a tendency for greater catecholamine responses under LOW (individualized peak concentrations: adrenaline MOD 0.55 ± 0.13 vs LOW 1.04 ± 0.37 nmol/L, P = 0.155; noradrenaline MOD 4.59 ± 0.86 vs LOW 7.11 ± 1.82 nmol/L, P = 0.082). The magnitude of post‐exercise hyperglycemia does not differ between equal volume low and moderate intensity RE sessions performed in the morning.     

Immunity in frail elderly: a randomized controlled trial of exercise and enriched foods

OBJECTIVE: To examine the effects of 17-wk physical exercise and enriched foods on cellular immune response (CIR) in frail elderly. METHODS: A total of 112 independently living, frail elderly men and women (mean age 79.2 +/- 5.9) received: twice weekly comprehensive, moderate intensity, progressive group exercise (group A, N = 26); daily enriched foods (group B, N = 31); both (group C, N = 29); or neither (group D, N = 26). Exercises focused on skills training. Foods were enriched with micronutrients with a high prevalence of deficiency in older people (at 25-100% the RDA). A social program and identical regular foods were offered as a control. CIR was measured by delayed-type hypersensitivity skin test response (DTH) against seven recall antigens expressed as the total number of positive responses and sum of diameters of all positive responses. RESULTS: No independent or interactive effect of enriched foods was observed. Therefore, exercise (groups A + C) was compared with no exercise (groups B + D). Nonexercising subjects showed an average decline of 0.5 responses compared with an unchanged responsiveness among exercising subjects (difference = 0.5, 95% CI: 0.04-0.89, P = 0.03 adjusted for baseline DTH, activity level, and micronutrient status). Nonexercising subjects had a larger decline in the sum of diameters of all positive responses than exercising subjects but the difference did not reach significance (adjusted difference = 2.1 mm, 95% CI:-1.0-4.8). CONCLUSION: Exercise may prevent or slow the age-related decline in immune response. Micronutrient enriched foods showed no effect. As infectious diseases can have debilitating or even fatal consequences for the elderly, prevention of the age-related decline in CIR could significantly improve their quality of life.     

Trunk exercise training improves muscle size,strength, and function in older adults: A randomized controlled trial

The aim of this study was to assess the effectiveness of a multimodal exercise program to increase trunk muscle morphology and strength in older individuals, and their associated changes in functional ability. Using a single‐blinded parallel‐group randomized controlled trial design, 64 older adults (≥60 years) were randomly allocated to a 12‐week exercise program comprising walking and balance exercises with or without trunk strengthening/motor control exercises; followed by a 6‐week walking‐only program (detraining; 32 per group). Trunk muscle morphology (ultrasound imaging), strength (isokinetic dynamometer), and functional ability and balance (6‐Minute Walk Test; 30 second Chair Stand Test; Sitting and Rising Test; Berg Balance Scale, Multi‐Directional Reach Test; Timed Up and Go; Four Step Square Test) were the primary outcome measures. Sixty‐four older adults (mean [SD]; age: 69.8 [7.5] years; 59.4% female) were randomized into two exercise groups. Trunk training relative to walking‐balance training increased (mean difference [95% CI]) the size of the rectus abdominis (2.08 [1.29, 2.89] cm²), lumbar multifidus (L4/L5:0.39 [0.16, 0.61] cm; L5/S1:0.31 [0.07, 0.55] cm), and the lateral abdominal musculature (0.63 [0.40, 0.85] cm); and increased trunk flexion (29.8 [4.40, 55.31] N), extension (37.71 [15.17, 60.25] N), and lateral flexion (52.30 [36.57, 68.02] N) strength. Trunk training relative to walking‐balance training improved 30‐second Chair Stand Test (5.90 [3.39, 8.42] repetitions), Sitting and Rising Test (1.23 [0.24, 2.23] points), Forward Reach Test (4.20 [1.89, 6.51] cm), Backward Reach Test (2.42 [0.33, 4.52] cm), and Timed Up and Go Test (?0.76 [?1.40, ?0.13] seconds). Detraining led to some declines but all outcomes remained significantly improved when compared to pre‐training. These findings support the inclusion of trunk strengthening/motor control exercises as part of a multimodal exercise program for older adults.     

MCT1 genetic polymorphism influence in high intensity circuit training: A pilot study

Monocarboxylate Transporter 1 (MCT1) mediates the transport of the main fraction of lactate across the sarcolemma. A common polymorphic MCT1 variant has been identified, but its role in high intensity exercise performance has not been defined. We investigated the influence of MCT1 A1470T polymorphism (rs1049434) on lactate accumulation after high intensity circuit training. Ten men aged 20–26 performed three controlled circuit training (CWT) sessions at 60%, 70%, and 80% of the 15 repetition maximum (15 RM), in non-consecutive days. CWT included three sets of a circuit of eight exercises, obtaining lactate measurements immediately after each set had been completed. Two independent variables were analysed: MTC1 genotypes according to the presence or absence of the A1470T polymorphism, and the intensity of circuit training. Genotype distributions were in Hardy–Weinberg equilibrium, being 30% wild-type, 50% heterozygotes, and 20% mutated homozygotes. Mean lactate concentration at 80% of 15 RM were significantly higher than the mean lactate values at the other intensities (p < 0.01). Significant differences between genetic groups were found in the lactate accumulation slope at 80% of 15 RM (p = 0.02) and in the maximal lactate concentration reached by all subjects in the study (L_max) (p = 0.03). The carriers of the A1470T polymorphism in the MTC1 gene seem to exhibit a worse lactate transport capability into the less active muscle cells for oxidation.     

Randomized controlled trial of training intensity in adiposity

The purpose of the study was to examine the effects of training intensity on abdominal fatness reduction and improvements of metabolic risk factors in Korean women (N=45, aged 45.4±7.3 yrs). Subjects were randomly assigned to control (CON, N=15) or low-intensity exercise (LIEX, N=15) or high-intensity exercise (HIEX, N=15). The LIEX and HIEX groups participated in a 12-wk exercise intervention at intensities of 40-50% and 70-75% of VO (2)max, respectively. Outcome assessments performed at baseline and at the end of 12-wk period included abdominal adipose tissues, VO (2)max, blood lipids, fasting glucose and insulin, and LPL- and HSL-mRNAs in abdominal subcutaneous adipose tissue (SAT). Unlike the CON group, women in the exercise groups had significant improvements in VO (2)max (+11%, P<0.001), SAT (-12%, P=0.026), TG (-23%, P=0.002), HDLC (+7.2%, P=0.013), insulin (-23%, P=0.037), and HOMA-IR (-25%, P=0.015) relative to baseline values. Changes in baseline CRF were in a dose-dependent manner based in intensity (-1.2±1.7, 2.1±2.8, and 4.7±3.2?ml/kg/min for CON, LIEX, and HIEX, respectively, P<0.001). We found no evidence that LIEX- and HIEX differ in their effects on abdominal adiposity, risk factors, and LPL- and HSL-mRNA expressions in SAT. In conclusion, the current findings suggest that low- and high-intensity exercise are equally effective in reducing abdominal adiposity and in improving risk factors.     

Isometric exercise and pain in patellar tendinopathy: A randomized crossover trial

ObjectivesThe aim of this study was to compare the acute effects of isometric versus dynamic resistance exercise on pain during a pain-provoking activity, and exercise-induced hypoalgesia in participants with patellar tendinopathy.DesignThis study was a pre-registered randomised crossover study. Participants were blinded to the study hypothesis.MethodsParticipants (N = 21) performed a single session of high load isometric resistance exercise or dynamic resistance exercise, in a randomised order separated by a 7-day washout period. Outcomes were assessed before, immediately after, and 45 min post-exercise. The primary outcome was pain intensity scored on a numeric pain rating scale (NRS; 0–10) during a pain-provoking single leg decline squat (SLDS). Secondary outcomes were pressure pain thresholds (PPTs) locally, distally and remotely, as well as tendon thickness.ResultsThere was a significant decrease in pain NRS scores (mean reduction 0.9, NRS 95%CI 0.1–1.7; p = 0.028), and increase in PPTs at the tibialis anterior muscle (mean increase 34 kPa 95%CI 9.5–58.5; p = 0.009) immediately post-exercise. These were not sustained 45 min post-exercise for pain (NRS) or PPTs (p > 0.05). There were no differences between exercise on any outcome.ConclusionsWhile patients with patellar tendinopathy decreased pain during SLDS in response to resistance training, but the magnitude was small. Contraction mode may not be the most important factor in determining the magnitude of pain relieving effects. Similarly, there were only small increases in PPTs at the tibialis anterior which were not superior for isometric exercise.     

Effect of exercise training on heart rate variability in patients with obstructive sleep apnea: A randomized controlled trial

While obstructive sleep apnea (OSA) increases chemoreflex, leading to an autonomic dysfunction in the long term, no studies have yet assessed the potential benefit of exercise on cardiac autonomic activity in these patients. The aim of this study was to evaluate potential improvement in cardiac autonomic function (CAF) measured through heart rate variability (HRV) after a 9‐month physical activity program in patients with OSA. Seventy‐four patients with moderate OSA, aged 40‐80 years, were randomly assigned to an exercise group (n = 36, 3 × 1 h/wk) or a control group (n = 38) during 9 months. Linear and nonlinear HRV parameters were measured during night using a Holter ECG. After 9 months, mean R‐R intervals increased in the exercise group without any changes in HRV parameters, while controls decreased global (standard deviation of normal‐to‐normal intervals, total power) and parasympathetic (root mean square successive difference of N‐Ns, very low frequency, high frequency, and standard deviation of the instantaneous beat‐to‐beat variability) indices of HRV (P < 0.05 for all). Significant correlations with moderate effect size were found between changes in apnea severity and changes in R‐R intervals (P < 0.05). Improvement in moderate‐to‐vigorous physical activity was also correlated to improvement in nocturnal oxygen parameters (P < 0.05). In conclusion, supervised community physical activity may prevent a decline in nighttime CAF observed in nontreated community‐dwelling patients with moderate OSA over a 9‐month period. Thus, beyond apnea‐hypopnea index improvement, exercise may be cardioprotective in OSA patients through bradycardia, CAF preservation, and VO_2peak increase.     

Endurance capacity and neuromuscular fatigue following high‐ vs moderate‐intensity endurance training: A randomized trial

High‐intensity exercise induces significant central and peripheral fatigue; however, the effect of endurance training on these mechanisms of fatigue is poorly understood. We compared the effect of cycling endurance training of disparate intensities on high‐intensity exercise endurance capacity and the associated limiting central and peripheral fatigue mechanisms. Twenty adults were randomly assigned to 6 weeks of either high‐intensity interval training (HIIT, 6‐8×5 minutes at halfway between lactate threshold and maximal oxygen uptake [50%Δ]) or volume‐matched moderate‐intensity continuous training (CONT, ~60‐80 minutes at 90% lactate threshold). Two time to exhaustion (TTE) trials at 50%Δ were completed pre‐ and post‐training to assess endurance capacity; the two post‐training trials were completed at the pretraining 50%Δ (same absolute intensity) and the “new” post‐training 50%Δ (same relative intensity). Pre‐ and post‐exercise responses to femoral nerve and motor cortex stimulation were examined to determine peripheral and central fatigue, respectively. HIIT resulted in greater increases in TTE at the same absolute and relative intensities as pre‐training (148% and 43%, respectively) compared with CONT (38% and ?4%, respectively) (P≤.019). Compared with pre‐training, HIIT increased the level of potentiated quadriceps twitch reduction (?34% vs ?43%, respectively, P=.023) and attenuated the level of voluntary activation reduction (?7% vs ?3%, respectively, P=.047) following the TTE trial at the same relative intensity. There were no other training effects on neuromuscular fatigue development. This suggests that central fatigue resistance contributes to enhanced high‐intensity exercise endurance capacity after HIIT by allowing greater performance to be extruded from the muscle.