Search results for "back"
showing 10 items of 2078 documents
Exploring directionality in spontaneous heart period and systolic pressure variability interactions in humans: implications in the evaluation of baro…
2004
Although in physiological conditions RR interval and systolic arterial pressure (SAP) are likely to interact in a closed loop, the traditional cross-spectral analysis cannot distinguish feedback (FB) from feedforward (FF) influences. In this study, a causal approach was applied for calculating the coherence from SAP to RR ( Ks-r) and from RR to SAP ( Kr-s) and the gain and phase of the baroreflex transfer function. The method was applied, compared with the noncausal one, to RR and SAP series taken from 15 healthy young subjects in the supine position and after passive head-up tilt. For the low frequency (0.04–0.15 Hz) spectral component, the enhanced FF coupling ( Kr-s = 0.59 ± 0.21, signi…
Associations of low back pain with neck pain: a study of industrial employees with 5-, 10-, and 28-year follow-ups.
2007
Low back pain (LBP) and neck pain (NP) are common among the adult population but relatively few reports exist on the associations between these. We examined cross-sectional and prospective relationships of LBP with NP in an employee cohort studied repeatedly over 28 years. Locally perceived pain was studied separately from pain with a radiating component. At baseline, adjusted for age, gender, and occupational class, the prevalence ratio (PR) of local NP for those with local LBP was 1.93 (95% CI 1.47–2.54), and for those with radiating LBP 2.16 (1.59–2.94), while the PR of radiating NP for those with local LBP was 1.51 (0.97–2.35) and for those with radiating LBP 3.24 (2.25–4.65). These ass…
Central and Peripheral Contributions to Fatigue after Electrostimulation Training
2006
Purpose: We examined the effect of 4 (WK4) and 8 wk (WK8) of neuromuscular electrical stimulation (NMES) training on both endurance time and mechanisms contributing to task failure. Methods: Ten males performed a fatiguing isometric contraction with the knee extensor muscles at 20% of maximal voluntary contraction (MVC) until exhaustion before (B), at WK4, and at WK8 of NMES training. The electromyographic (EMG) activity and muscle activation obtained under MVC were recorded before and after the fatiguing task to assess central fatigue. Torque and EMG responses obtained under electrically evoked contractions were examined before and after the fatiguing task to analyze peripheral fatigue. Re…
Neuromuscular fatigue differs with biofeedback type when performing a submaximal contraction
2007
The aim of the study was to examine alterations in contractile and neural processes in response to an isometric fatiguing contraction performed with EMG feedback (constant-EMG task) when exerting 40% of maximal voluntary contraction (MVC) torque with the knee extensor muscles. A task with a torque feedback (constant-torque task) set at a similar intensity served as a reference task. Thirteen men (26+/-5 yr) attended two experimental sessions that were randomized across days. Endurance time was greater for the constant-EMG task compared with the constant-torque task (230+/-156 s vs. 101+/-32s, P0.01). Average EMG activity for the knee extensor muscles increased from 33.5+/-4.5% to 54.7+/-21.…
Subjective fixation disparity affected by dynamic asymmetry, resting vergence, and nonius bias.
2011
PURPOSE This study was undertaken to investigate how subjectively measured fixation disparity can be explained by (1) the convergent-divergent asymmetry of vergence dynamics (called dynamic asymmetry) for a disparity vergence step stimulus of 1° (60 arc min), (2) the dark vergence, and (3) the nonius bias. METHODS Fixation disparity, dark vergence, and nonius bias were measured subjectively using nonius lines. Dynamic vergence step responses (both convergent and divergent) were measured objectively. RESULTS In 20 subjects (mean age, 24.5 ± 4.3 years, visual acuity, ≥1.0; all emmetropic except for one with myopia, wearing contact lenses), multiple regression analyses showed that 39% of the v…
Therapeutic aquatic exercise in the treatment of low back pain: a systematic review.
2008
Objective: To examine the effectiveness of therapeutic aquatic exercise in the treatment of low back pain. Design: A systematic review. Methods: A search was performed of PEDro, CINAHL (ovid), PUBMED, Cochrane Controlled Trials Register and SPORTDiscus databases to identify relevant studies published between 1990 and 2007. Population: Adults suffering from low back pain. Intervention: All types of therapeutic aquatic exercise. Comparison: All clinical trials using a control group. Outcomes: Oswestry Disability Index, McGill Pain Questionnaire, subjective assessment scale for pain (e.g. visual analogue scale) and number of work days lost as a direct result of low back pain. Methodological q…
The role of obesity and physical activity in non-specific and radiating low back pain: The Young Finns study
2013
Objective To study the effects of obesity, physical activity, and change in physical activity on the incidence of low back pain and explore whether obesity modifies the effects of physical activity. Methods As part of the ongoing Young Finns Study, 1224 subjects aged 24–39 years free from low back pain during the preceding 12 months at baseline in 2001 were included. Obesity was defined based on the body mass index (BMI) and waist circumference, and physical activity was assessed by the metabolic equivalent of task (MET) index in 2001 and 2007. Results Abdominal obesity, defined by an increased waist circumference, was associated with an increased incidence of radiating low back pain (adjus…
Long-term sensorimotor and therapeutical effects of a mild regime of prism adaptation in spatial neglect
2015
International audience; Spatial neglect (SN) is commonly associated with poor functional outcome. Adaptation to a rightward optical deviation of vision has been shown to benefit to SN rehabilitation. The neurophysiological foundations and the optimal modalities of prism adaptation (PA) therapy however remain to be validated. This study is aimed at exploring the long-term sensory-motor, cognitive and functional effects produced by weekly PA sessions over a period of four weeks. A double-blind, monocentric randomized and controlled trial (RCT) was carried out. Twenty patients with left SN secondary to stroke were included, 10 in the “prism” group and 10 in the “control” group. The sensory-mot…
Use of Visual Feedback During Jump-Squat Training Aids Improvement in Sport-Specific Tests in Athletes.
2020
Vanderka, M, Bezak, A, Longova, K, Krcmar, M, and Walker, S. Use of visual feedback during jump-squat training aids improvement in sport-specific tests in athletes. J Strength Cond Res 34(8): 2250-2257, 2020-This study investigated the effects of instantaneous performance feedback during the jump-squat exercise over a 6-week training period. Twenty-five strength-trained athletes were randomly divided into an instant feedback (n = 13, half-squat 3-repetition maximum (3RM)/body mass = 2.38 ± 0.19) or a nonfeedback (n = 12, half-squat 3RM/body mass = 2.03 ± 0.44) group. Both groups performed the same training program (3 × week), consisting of 4 sets of 8 repetitions (weeks 1-3) and 8 sets of 4…
Muscular performance after a 3 month progressive physical exercise program and 9 month follow-up in subjects with low back pain. A controlled study
2007
The purpose of this study was to assess, in subjects with low back pain, the changes and their permanence in muscular performance after a 3 month progressive physical exercise program. Ninety subjects with chronic low back pain participated in the study. The study design was controlled and it was carried out in three groups: intensive training, home exercise, and control group. Isometric and dynamic muscle strength of the trunk and lower limb were measured, at the beginning of the study and after the 3 months exercise program, and then during each of the follow-up sessions. The Oswestry Index and back pain intensity were also determined. Both exercise groups received benefit from the progre…