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During soccer matches, performance decrements have been reported that relate to both physical abilities and technical skills. To investigate the effects of low-frequency electrical stimulation LFES (VeinoplusSport®, Ad Rem Technology, France) administered during half-time recovery on performance alterations during the second half. Twenty-two highly trained young players undertook a soccer-match simulation (SAFT90). During half-time, they were randomly assigned to LFES group or Placebo group. Each half was split into 3 bouts of 12 minutes. Following each bout, maximal strike speed (MSS), sprint test (ST), maximal sprint accelerations (MA) and metabolic power (MP) were determined in both groups. Arterial (AF) and venous flows (VF) were measured at rest and at the end of half-time. LEFS group exhibited beneficial effects on performance compared to the Placebo group with a likely effect for MSS, ST, MA, and a possible effect for MP. AF and VF increased statistically more in LEFS group compared to Placebo group. The use of specific calf-pump LFES during half-time of a youth simulated soccer match attenuated the decrease in performance during the second half compared to Placebo group. This effect is most marked at the beginning of the second half with regards to explosive parameters. [ABSTRACT FROM AUTHOR]

Purpose: Both constant and intermittent acute aerobic exercises have been found to decrease arterial stiffness. However, direct comparisons of these two types of exercise are sparse. It is not known which type of exercise has the greatest effect.Methods: We evaluated the haemodynamic responses in 15 males (age 48.5 ± 1.3 years; BMI 27.5 ± 0.8 kg m-2) following acute constant (CE) and intermittent cycling exercise (IE). Duration and heart rate were matched during both exercises (131.8 ± 3.2 bpm for CE and 132.0 ± 3.1 bpm for IE). Central and peripheral arterial stiffness was assessed through pulse wave velocity (PWV). Plasma concentrations of nitric oxide (NO), atrial natriuretic peptide (ANP), blood lactate, noradrenaline, and adrenaline were measured before and after each exercise.Results: Central (+ 1.8 ± 7.4 and - 6.5 ± 6.8% for CE and IE) and upper limb PWV (+ 2.7 ± 6.2 and - 8 ± 4.6% for CE and IE) were not significantly altered although a small decrease (small effect size) was observed after IE. However, lower limb PWV significantly decreased after exercises (- 7.3 ± 5.7 and - 15.9 ± 4% after CE and IE), with a larger effect after IE.Conclusions: Greater decrease in lower limb PWV occurred after IE despite greater heart rate. This may be due to the higher blood levels of lactate during IE, while NO, ANP, noradrenaline, and adrenaline levels remained not statistically different from CE. These results underlined the importance of lactate in triggering the post-exercise vascular response to exercise, as well as its regional characteristic. [ABSTRACT FROM AUTHOR]

The autonomic nervous activity was assessed following supramaximal exercise through heart rate (HR) and blood pressure (BP) variability (HRV and BPV) and baroreflex sensitivity (BRS). The beat-to-beat HR and BP were recorded during the supine and standing states before (PRE) and at 60 (R60) and 120 min (R120) following single (one Wingate, 1W) and multiple sprint intervals (four Wingates interspersed with 4 min of light cycling, 4W). The supine low frequency (LF) component was increased ( P<0.001) and the high frequency (HF) was reduced ( P<0.01) at R60 (LF, 178.1 ± 11.0; HF, 74.8 ± 10.5) compared with PRE (LF, 140.2 ± 7.4; HF, 110.4 ± 7.2) after both exercises. Supine systolic BPV LF:HF was higher at R60 (4.6 ± 1.4) compared with PRE (6.8 ± 2.4) only after 4W ( P=0.035). Supine BRS was lower ( P<0.001) at R60 (6.8 ± 1.1) than at PRE (15.3 ± 1.8) and R120 (11.3 ± 1.3). BRS at R120 remained lower after 4W ( P=0.02). Standing BRS was less ( P<0.001) at R60 (2.3 ± 0.5) than at PRE (5.6 ± 0.8) or R120 (3.7 ± 0.6) and returned to PRE values only after 1W. We concluded that (a) autonomic balance is shifted to a greater sympathetic and less parasympathetic activation following both types of exercise, (b) it takes longer than 1 h to recover following supramaximal exercise and (c) the recovery is longer after 4W than 1W. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effects of calf compression sleeves on running performance and on calf tissue oxygen saturation (StO2) at rest before exercise and during recovery period. 14 moderately trained athletes completed 2 identical sessions of treadmill running with and without calf compression sleeves in randomized order. Each session comprised: 15 min at rest, 30 min at 60% maximal aerobic velocity determined beforehand, 15 min of passive recovery, a running time to exhaustion at 100% maximal aerobic velocity, and 30 min of passive recovery. Calf StO2 was determined by near infra-red spectroscopy and running performance by the time to exhaustion. Compression sleeves increased significantly StO2 at rest before exercise (+ 6.4 ± 1.9%) and during recovery from exercise (+ 7.4 ± 1.7% and + 10.7 ± 1.8% at 20th and 30th min of the last recovery period, respectively). No difference was observed between the times to exhaustion performed with and without compression sleeves (269.4 ± 18.4 s and 263.3 ± 19.8 s, respectively). Within the framework of this study, the compression sleeves do not improve running performance in tlim. However the StO2 results argue for further interest of this garment during effort recovery. [ABSTRACT FROM AUTHOR]

Study design:Cross-over study.Objective:To determine the effect of strenuous wheelchair exercise on oxygen uptake ( ), muscle activity and propulsion cycle timing (including the push time and recovery time during one full arm cycle).Setting:Laboratory of Sport Sciences at the University of France-Comte in France.Methods:Two exercise bouts of 6-min duration were performed at a constant workload: (1) non-fatigable exercise (moderate workload) and (2) fatigable exercise (heavy workload). Measurement of , surface electromyographic activity (EMG) from shoulder muscles, and temporal parameters of wheelchair ergometer propulsion were collected from eight able-bodied men (26±4 years).Results:A progressive increase in associated with EMG alterations (P<0.05), and a decrease of the cycle and recovery time (P<0.05) during the heavy exercise. Whereas the push time remained constant, an increased muscle activation time (P<0.05) was found during heavy exercise.Conclusion:Observations during wheelchair ergometry indicate the development of fatigue and inefficient muscle coordination, which may contribute to deleterious stress distributions at the shoulder joint, increasing susceptibility to injury.Spinal Cord (2007) 45, 468–474; doi:10.1038/sj.sc.3101989; published online 24 October 2006 [ABSTRACT FROM AUTHOR]

STUDY DESIGN:: Before and after investigation of the effects of a wheelchair ergometer Training programme. OBJECTIVE:: To investigate the effects of an original interval-training programme on work capacity and cardiorespiratory variables with spinal cord-injured persons (SCIP's) on a wheelchair-specific ergometer. SETTING:: BESANCON, FRANCE. METHODS:: Seven SCIP's (male) performed 45?min of wheelchair ergometry three times per week, for 6 weeks. Training effects on maximal dynamic performance and endurance capacity were studied by comparison of performance and cardiorespiratory responses observed during both a maximal progressive test (10?W/2?min) and the same training session performed before and after training. RESULTS:: Training induced significant improvements in maximal tolerated power (+19.6%), in peak oxygen consumption (VO2+16%), and in oxygen pulse (O2p,+18.7%).At ventilatory threshold, significant improvements were also observed in power output (+63%), VO2VT(+ 34.1), ventilation VEVT(+ 37.1%), and V2pVT(+ 19.9% ). Heart rate and ventilation were significantly lower (-11 and -14.6%, respectively) after training at the same work rate, while VO2 was unchanged. Between the first and the last training session, the total physical work was improved by 24.7%, whereas heart rate was unchanged. CONCLUSION:: An interval-training programme individualised to each paraplegic subject using a wheelchair ergometer can significantly improve the fitness level and endurance capacity.Spinal Cord (2003) 41, 451-456. doi:10.1038/sj.sc.3101475 [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate the influence of an interval training program for the upper limbs on cardiorespiratory fitness and walking ability in elderly patients after total hip joint arthroplasty. DESIGN: A randomized controlled trial. After surgery, control and training groups started general rehabilitation. Training group combined it with an arm-interval exercise program (3 sessions of 30 minutes per week, for 6 weeks). SUBJECTS: Patients were assigned randomly to control (n = 7) and training groups (n = 7). METHODS: Incremental exercise tests were carried out until exhaustion on an arm crank ergometer 1 month before and 2 months after surgery. A 6-minute walk test was also performed 2 months after surgery. RESULTS: VO2 peak increased significantly in the training group (p = 0.0424) and did not change in the control group. The difference in VO2 peak change between the groups was significant (p = 0.0362, +19.2% in the training group and -3.5% in the control group). In the walking test the training group covered a significantly longer distance than did the control group (p = 0.0055, 396.4 metres and 268.1 metres, respectively). CONCLUSION: These results stress the importance of physical training in a rehabilitation program after total hip joint arthroplasty and this should be considered for improving the current practices in rehabilitation. [ABSTRACT FROM AUTHOR]

Investigates the hypothesis that oxygen uptake kinetics at the onset of heavy exercise would be altered in a state of muscle fatigue and prior metabolic acidosis. Level of oxygen uptake kinetics after prior sprint exercise; Cardiac output in the first two minutes of the second heavy exercise bout; Normalized integrated surface electromyography of four leg muscles and normalized mean power frequency between exercise bouts.

Compares the effects of a rehabilitation program on the perceived exertion and the cardioventilatory responses during exercise in healthy people and paraplegics. Implication of rehabilitation exercise for the maximal tolerated power and peak oxygen uptake; Measurement of heart rate and perceived exertion and pain; Problems regarding the thermal regulation disorders of paraplegics.

BACKGROUND:: Various combinations of training intensity, duration and frequency are often proposed to people with spinal cord injuries in order to improve their fitness. However, no consensus about a specific training program has been reached for such a population. OBJECTIVE:: This study investigated the effects of a short interval training program specifically designed for patients with spinal cord injuries. METHODS:: Paraplegic men performed 30-min wheelchair ergometry three times per week, for 4 weeks. Maximal dynamic performance and endurance capacity were studied before and after the training program with an incremental test (10 W/2 min) until volitional fatigue and a constant work rate test, respectively. Cardiorespiratory responses were continuously studied during each of these tests. RESULTS:: Training induced significant improvement in maximal tolerated power (+27.9%), and in peak oxygen consumption (&Vdot;O2, +18.5%). After training the subjects were able to maintain the load applied during the constant test (total mechanical work +210.7%), for a significantly longer time. The heart rate, &Vdot;O2 and ventilation values observed when the volunteers ended their first constant load test were significantly higher (+10%, +10%, +40% respectively) than those obtained after a similar time period during the second constant load test which was performed after the training program. CONCLUSION:: After this short training period, with an appropriate combination of different types of training, duration, intensity and frequency exercises, we observed a significant improvement in the fitness level and endurance capacity of paraplegic subjects.Spinal Cord (2001) 39, 532–537. [ABSTRACT FROM AUTHOR]

Objective: To investigate the influence of an arm-interval exercise program for the upper limbs on health status and walking ability in elderly patients after total hip arthroplasty.Design: A randomized controlled investigation. After surgery, a control group started a general rehabilitation program, and a training group combined it with an arm-interval exercise program.Subjects: Fourteen patients (age 75.1 +/- 4.8 years) were randomly assigned to the control group (n = 7) and the training group (n = 7).Methods: A Western Ontario and MacMaster University (WOMAC) Osteoarthritis Index was completed and an incremental exercise test on an arm crank ergometer was also performed 1 month before (T [-1] ) and 2 months after surgery (T[2]). Moreover, a 6-minute walk test was performed at T [2].Results: Both groups significantly improved all dimensions of WOMAC, except in WOMAC physical function subscale in the control group. The training group covered a significantly longer distance in the walking test than the control group and also presented significantly higher VO2 peak value at T[2]. Correlation analyses indicate that VO2 peak value and the distance covered in the 6-minute walking test were significantly associated with functional status. After calculating the ratio distance covered/score at WOMAC physical function, we observed a significantly higher ratio value in the training group than in the control group.Conclusion: Preliminary results indicate that the improvement in physical fitness and functional status of the training group seems to be associated with better health status. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the effects of compression sleeves (CS) on the stride biomechanical parameters and the performance in running on treadmill. The study includes 10 men who are moderately trained in endurance and measures the vertical displacement of the gravity centre through kinematic arm. Results indicate CS limits the stride alteration which was caused by a change of intensity.