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Said Ahmaidi

Bio: Said Ahmaidi is an academic researcher from University of Picardie Jules Verne. The author has contributed to research in topics: Isometric exercise & Ventilatory threshold. The author has an hindex of 46, co-authored 172 publications receiving 6252 citations.


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Journal ArticleDOI
TL;DR: Parasympathetic reactivation is highly impaired after RS exercise and appears to be mainly related to anaerobic process participation.
Abstract: The purpose of this study was to examine the effects of muscular power engagement, anaerobic participation, aerobic power level, and energy expenditure on postexercise parasympathetic reactivation....

251 citations

Journal ArticleDOI
TL;DR: Because RS and ExpS were equally efficient at enhancing maximal sprinting speed, RS training-induced improvements in RSA were likely more related to progresses in the ability to change direction than ExpS.
Abstract: To compare the effects of explosive strength (ExpS) vs. repeated shuttle sprint (RS) training on repeated sprint ability (RSA) in young elite soccer players, 15 elite male adolescents (14.5 ± 0.5 years) performed, in addition to their soccer training program, RS (n = 7) or ExpS (n = 8) training once a week for a total of 10 weeks. RS training consisted of 2-3 sets of 5-6 × 15- to 20-m repeated shuttle sprints interspersed with 14 seconds of passive or 23 seconds of active recovery (≈2 m·s⁻¹); ExpS training consisted of 4-6 series of 4-6 exercises (e.g., maximal unilateral countermovement jumps (CMJs), calf and squat plyometric jumps, and short sprints). Before and after training, performance was assessed by 10 and 30 m (10 and 30 m) sprint times, best (RSAbest) and mean (RSAmean) times on a repeated shuttle sprint ability test, a CMJ, and a hopping (Hop) test. After training, except for 10 m (p = 0.22), all performances were significantly improved in both groups (all p's < 0.05). Relative changes in 30 m (-2.1 ± 2.0%) were similar for both groups (p = 0.45). RS training induced greater improvement in RSAbest (-2.90 ± 2.1 vs. -0.08 ± 3.3%, p = 0.04) and tended to enhance RSAmean more (-2.61 ± 2.8 vs. -0.75 ± 2.5%, p = 0.10, effect size [ES] = 0.70) than ExpS. In contrast, ExpS tended to induce greater improvements in CMJ (14.8 ± 7.7 vs. 6.8 ± 3.7%, p = 0.02) and Hop height (27.5 ± 19.2 vs. 13.5 ± 13.2%, p = 0.08, ES = 0.9) compared with RS. Improvements in the repeated shuttle sprint test were only observed after RS training, whereas CMJ height was only increased after ExpS. Because RS and ExpS were equally efficient at enhancing maximal sprinting speed, RS training-induced improvements in RSA were likely more related to progresses in the ability to change direction.

249 citations

Journal ArticleDOI
TL;DR: The results illustrate the potential of resting, exercise and post-exercise HR measurements for both assessing and predicting the impact of aerobic training on endurance running performance.
Abstract: The aims of the present study were to (1) assess relationships between running performance and parasympathetic function both at rest and following exercise, and (2) examine changes in heart rate (HR)-derived indices throughout an 8-week period training program in runners. In 14 moderately trained runners (36 ± 7 years), resting vagal-related HR variability (HRV) indices were measured daily, while exercise HR and post-exercise HR recovery (HRR) and HRV indices were measured fortnightly. Maximal aerobic speed (MAS) and 10 km running performance were assessed before and after the training intervention. Correlations (r > 0.60, P 0.5% (responders), resting vagal-related indices showed a progressively increasing trend (time effect P = 0.03) and qualitative indications of possibly and likely higher values during week 7 [+7% (90% CI −3.7;17.0)] and week 9 [+10% (90% CI −1.5;23)] compared with pre-training values, respectively. Post-exercise HRV showed similar changes, despite less pronounced between-group differences. HRR showed a relatively early possible decrease at week 3 [−20% (90% CI −42;10)], with only slight reductions near the end of the program. The results illustrate the potential of resting, exercise and post-exercise HR measurements for both assessing and predicting the impact of aerobic training on endurance running performance.

230 citations

Journal ArticleDOI
TL;DR: HIT was more effective than RS training at improving postexercise parasympathetic function and physical performance, and HRRtau, which was more sensitive to training than HRV indices, seems to be a useful performance-related measurement.
Abstract: Repeated supramaximal exercise training is an efficient means of improving both aerobic and anaerobic energy system capacities. However, the influence of different levels of supramaximal training on parasympathetic function is unknown.Purpose:To compare the effects of repeated-sprint (RS) ve

226 citations

Journal ArticleDOI
TL;DR: Postexercise heart rate recovery (HRR) recovery and HR variability (HRV) are commonly used in noninvasive assessment procedures for the determination of cardiovascular parasympathetic function.
Abstract: postexercise heart rate (HR) recovery (HRR) and HR variability (HRV) are commonly used in noninvasive assessment procedures for the determination of cardiovascular parasympathetic function ([3][1], [8][2], [9][3], [15][4], [20][5]). Evaluation of cardiovascular parasympathetic function is important

222 citations


Cited by
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TL;DR: These guidelines are a revision of the 1995 standards of the AHA that addressed the issues of exercise testing and training and current issues of practical importance in the clinical use of these standards are considered.
Abstract: The purpose of this report is to provide revised standards and guidelines for the exercise testing and training of individuals who are free from clinical manifestations of cardiovascular disease and those with known cardiovascular disease. These guidelines are intended for physicians, nurses, exercise physiologists, specialists, technologists, and other healthcare professionals involved in exercise testing and training of these populations. This report is in accord with the “Statement on Exercise” published by the American Heart Association (AHA).1 These guidelines are a revision of the 1995 standards of the AHA that addressed the issues of exercise testing and training.2 An update of background, scientific rationale, and selected references is provided, and current issues of practical importance in the clinical use of these standards are considered. These guidelines are in accord with the American College of Cardiology (ACC)/AHA Guidelines for Exercise Testing.3 ### The Cardiovascular Response to Exercise Exercise, a common physiological stress, can elicit cardiovascular abnormalities that are not present at rest, and it can be used to determine the adequacy of cardiac function. Because exercise is only one of many stresses to which humans can be exposed, it is more appropriate to call an exercise test exactly that and not a “stress test.” This is particularly relevant considering the increased use of nonexercise stress tests. ### Types of Exercise Three types of muscular contraction or exercise can be applied as a stress to the cardiovascular system: isometric (static), isotonic (dynamic or locomotory), and resistance (a combination of isometric and isotonic).4,5 Isotonic exercise, which is defined as a muscular contraction resulting in movement, primarily provides a volume load to the left ventricle, and the response is proportional to the size of the working muscle mass and the intensity of exercise. Isometric exercise is defined as a muscular contraction without movement (eg, handgrip) and imposes greater pressure than volume …

2,964 citations

Journal ArticleDOI
TL;DR: In four important domains of quality of life (QoL) (Chronic Respiratory Questionnaire (CRQ) scores for dyspnoea, fatigue, emotional function and mastery), the effect was larger than the minimal clinically important difference (MCID) of 0.4%.
Abstract: Background The widespread application pulmonary rehabilitation in chronic obstructive pulmonary disease (COPD) should be preceded by demonstrable improvements in function attributable to the programs. This review updates that reported by Lacasse et al Lancet 1996; 748:1115-1119. Objectives To determine the impact of rehabilitation on health-related quality of life (QoL) and exercise capacity in patients with COPD. Search strategy The 14 randomized controlled trials (RCTs) included in the original meta-analysis were included. Additional RCTs were identified from the Cochrane Airways Group's registry of COPD RCTs using the strategy: [exp, lung diseases, obstructive] and [exp, rehabilitation or exp, exercise therapy] and [research design or longitudinal studies or evaluation study or randomized controlled trial]. Abstracts presented at American Thoracic Society 1980-2000, American College of Chest Physicians 1980-2000 and European Respiratory Society 1987-2000 were also searched. Selection criteria RCTs of rehabilitation in patients with COPD in which quality of life (QoL) and/or functional (FEC) or maximal (MEC) exercise capacity were measured. Rehabilitation was defined as exercise training for at least 4 weeks with or without education and/or psychological support. Control groups received conventional community care without rehabilitation. Data collection and analysis Weighted mean differences (WMD) were calculated using a random-effects model. Missing data from the primary study reports were requested from the authors. Main results 23 RCTs met the inclusion criteria. Statistically significant improvements were found for all the outcomes. In three important domains of QoL (Chronic Respiratory Questionnaire scores for Dyspnea, Fatigue and Mastery), the effect was larger than the minimal clinically important difference of 0.5 units using this instrument. For example Dyspnoea score: WMD 0.98 units, 95% Confidence Interval (95% CI) 0.74 - 1.22 units; n=9 trials. For FEC and MEC, the effect was small and a little below the threshold of clinical significance for the 6- minute walking distance: WMD 49 m, 95% CI: 26 - 72 m; n=10 trials. Reviewer's conclusions Rehabilitation relieves dyspnea and fatigue and enhances patients' sense of control over their condition. These improvements are moderately large and clinically significant. The average improvement in exercise capacity was modest. Rehabilitation forms an important component of the management of COPD.

1,863 citations

Journal ArticleDOI
TL;DR: Linda Nici, Claudio Donner, Emiel Wouters, Richard Zuwallack, Nicolino Ambrosino, Jean Bourbeau, Mauro Carone, Bartolome Celli, Marielle Engelen, Bonnie Fahy, Chris Garvey, Roger Goldstein, Rik Gosselink, Suzanne Lareau, Neil MacIntyre, Francois Maltais, Mike Morgan, Denis O’Donnell, Christian Prefault, Jane Reardon, Carolyn Rochester
Abstract: Linda Nici, Claudio Donner, Emiel Wouters, Richard Zuwallack, Nicolino Ambrosino, Jean Bourbeau, Mauro Carone, Bartolome Celli, Marielle Engelen, Bonnie Fahy, Chris Garvey, Roger Goldstein, Rik Gosselink, Suzanne Lareau, Neil MacIntyre, Francois Maltais, Mike Morgan, Denis O’Donnell, Christian Prefault, Jane Reardon, Carolyn Rochester, Annemie Schols, Sally Singh, and Thierry Troosters, on behalf of the ATS/ERS Pulmonary Rehabilitation Writing Committee

1,836 citations

Journal ArticleDOI
01 May 2007-Chest
TL;DR: Substantial new evidence that pulmonary rehabilitation is beneficial for patients with COPD and other chronic lung diseases and several areas of research provide opportunities for future research that can advance the field and make rehabilitative treatment available to many more eligible patients in need.

1,259 citations

01 Jan 2016
Abstract: Thank you for downloading textbook of work physiology physiological bases of exercise. As you may know, people have look hundreds times for their chosen novels like this textbook of work physiology physiological bases of exercise, but end up in infectious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they cope with some harmful virus inside their desktop computer.

1,015 citations