W. Darlene Reid

Inspiratory muscle training in adults with chronic obstructive pulmonary disease: An update of a systematic review

The purpose was to update an original systematic review to determine the effect of inspiratory muscle training (IMT) on inspiratory muscle strength and endurance, exercise capacity, dyspnea and quality of life for adults with chronic obstructive pulmonary disease (COPD). The original MEDLINE and CINAHL search to August 2003 was updated to January 2007 and EMBASE was searched from inception to January 2007. Randomized controlled trials, published in English, with adults with stable COPD, comparing IMT to sham IMT or no intervention, low versus high intensity IMT, and different modes of IMT were included. Nineteen of 274 articles in the original search met the inclusion criteria. The updated search revealed 17 additional articles; 6 met the inclusion criteria, all of which compared targeted, threshold or normocapneic hyperventilation IMT to sham IMT. An update of the sub-group analysis comparing IMT versus sham IMT was performed with 10 studies from original review and 6 from the update. Sixteen meta-analyses are reported. Results demonstrated significant improvements in inspiratory muscle strength (PI(max), PI(max) % predicted, peak inspiratory flow rate), inspiratory muscle endurance (RMET, inspiratory threshold loading, MVV), exercise capacity (Ve(max), Borg Score for Respiratory Effort, 6MWT), Transitional Dyspnea Index (focal score, functional impairment, magnitude of task, magnitude of effort), and the Chronic Respiratory Disease Questionnaire (quality of life). Results suggest that targeted, threshold or normocapneic hyperventilation IMT significantly increases inspiratory muscle strength and endurance, improves outcomes of exercise capacity and one measure of quality of life, and decreases dyspnea for adults with stable COPD.

Different effects of strenuous eccentric exercise on the accumulation of neutrophils in muscle in women and men

Abstract The purpose of this study was to evaluate the sex differences in delayed onset muscle soreness (DOMS), torque, and accumulation of technetium-99m (Tc-99m) neutrophils in eccentric-exercised muscle. A group of 10 female and 12 male subjects took part in this study. The subjects completed a pre-test using the descriptor differential scale (DDS) to describe DOMS, and tests of concentric and eccentric torque of the right quadriceps. A volume of 100 ml of blood was taken by venipuncture for neutrophil labelling in the early morning of the exercise day. The Tc-99m neutrophils were re-infused intravenously before the eccentric exercise. The exercise stimulus consisted of 300 eccentric repetitions of the right quadriceps muscles. Radionuclide images of both quadriceps muscles (lateral views) were taken at 2 and 4 h. The DDS, and concentric and eccentric torques of the quadriceps were subsequently evaluated at 0 h, 2, 4, 20 and 24 h post-exercise. The presence of Tc-99m neutrophils was greater in the exercised leg than the non-exercised leg at 2 and 4 h post-exercise (P ≤ 0.013) and greater in the exercised leg of the women compared to the men at 2 h (P = 0.03). The DOMS had increased post-exercise (P < 0.001) and torque had decreased post-exercise (P ≤ 0.002) but the patterns were different between the sexes. We concluded that the sex influences the presence of Tc-99m neutrophils in the exercised muscle following eccentric exercise. In addition, different patterns of DOMS and torque were observed between the sexes after eccentric exercise, and require further investigation.

Diagnostic techniques in acute compartment syndrome of the leg.

Objectives: To review the efficacy of the current diagnostic methods of acute compartment syndrome (ACS) after leg fractures. Data Sources: A Medline (PubMed) search of the English literature extending from 1950 to May 2007 was performed using “compartment syndromes” as the main key word. Also a manual search of orthopaedic texts was performed. Study Selection and Extraction: The results were limited to articles involving human subjects. Of 2605 primary titles, 489 abstracts limited to compartment syndromes in the leg and 577 articles related to the diagnosis of compartment syndromes were identified and their abstracts reviewed. Further articles were identified by reviewing the references. Sixty-six articles were found to be relevant to diagnostic techniques for compartment syndrome in the leg and formed the basis of this review. Conclusions: Early diagnosis of an ACS is important. Despite its drawbacks, clinical assessment is still the diagnostic cornerstone of ACS. Intracompartmental pressure measurement can confirm the diagnosis in suspected patients and may have a role in the diagnosis of this condition in unconscious patients or those unable to cooperate. Whitesides suggests that the perfusion of the compartment depends on the difference between the diastolic blood pressure and the intracompartmental pressure. They recommend fasciotomy when this pressure difference, known as the Δp, is less than 30 mm Hg. Access to a precise, reliable, and noninvasive method for early diagnosis of ACS would be a landmark achievement in orthopaedic and emergency medicine.

Top-Cited Articles in Rehabilitation

OBJECTIVE To identify the 100 top-cited articles ever published in rehabilitation journals and to analyze their characteristics as a quantitative approach to investigating the quality and evolution of rehabilitation research. DATA SOURCES The Institute for Scientific Information Web of Knowledge Database and the 2007 and 2008 Journal Citation Report Science Editions were used to retrieve the 100 top-cited articles from 30 rehabilitation dedicated journals. STUDY SELECTION The 100 top-cited articles included randomized controlled trials, case-control studies, case series studies, case reports, methodologic studies, systematic reviews, narrative reviews, and expert opinions. DATA EXTRACTION Two independent reviewers performed data extraction from the retrieved articles and compared their results. The Sacketts initial rules of evidence were used to categorize the type of study design as well as to evaluate the level of evidence provided by the results of the 100 top-cited articles. DATA SYNTHESIS Among the 45,700 articles published in these journals, the 100 top-cited articles were published between 1959 and 2002 with an average of 200 citations an article (range, 131-1109). Top-cited articles were all English-language, primarily from North America (United States=67%; Canada=11%) and published in 11 journals led by the Archives of Physical Medicine and Rehabilitation. Eighty-four percent of the articles were original publications and were most commonly prospective (76%) case series studies (67%) that used human subjects (96%) providing level 4 evidence. Neurorehabilitation (41%), disability (19%), and biomechanics (18%) were the most common fields of study. CONCLUSIONS We demonstrated that methodologic observational studies performed in North America and published in English have had the highest citations in rehabilitation journals.

Preservation of eccentric strength in older adults: Evidence, mechanisms and implications for training and rehabilitation

Overall reductions in muscle strength typically accompany the aging process. However, older adults show a relatively preserved capacity of producing eccentric strength. The preservation of eccentric strength in older adults is a well-established phenomenon, occurring indiscriminately across different muscle groups, independent of age-related architectural changes in muscle structure and velocity of movement. The mechanisms for the preservation of eccentric strength appear to be mechanical and cellular in origin and include both passive and active elements regulating muscle stiffness. The age-related accumulation of non-contractile material in the muscle-tendon unit increases passive stiffness, which might offer mechanical advantage during eccentric contractions. In addition, the preserved muscle tension and increased instantaneous stiffness of old muscle fibers during stretch increase active stiffness, which might enhance eccentric strength. The fact that the preservation of eccentric strength is present in people with chronic conditions when compared to age-matched healthy controls indicates that the aging process per se does not exclusively mediate the preservation of eccentric strength. Physical inactivity, which is common in elderly and people with chronic conditions, is a potential factor regulating the preservation of eccentric strength. When compared to concentric strength, the magnitude of preservation of eccentric strength in older adults ranges from 2% to 48% with a mean value of 21.6% from all studies. This functional reserve of eccentric strength might be clinically relevant, especially to initiate resistance training and rehabilitation programs in individuals with low levels of strength.

Falls in patients with chronic obstructive pulmonary disease: a call for further research.

Chronic obstructive pulmonary disease (COPD) is a respiratory disease that results in airflow limitation and respiratory distress. The effects of COPD, however, are not exclusively limited to respiratory function and people with COPD face many non-respiratory manifestations that affect both function and mobility. Deficits in function and mobility have been associated with an increased risk for falling in older adults. The purpose of this study was to provide a theoretical framework to identify risks factors for falls in people with COPD. We have analyzed the literature to identify possible relationships between pathophysiological changes observed in COPD and common risk factors for falls. Well-established fall risk factors in people with COPD include lower limb muscle weakness and impaired activities of daily living. Other intrinsic risk factors such as gait and balance deficits, nutritional depletion, malnutrition, depression, cognitive impairments and medications are possible risk factors that need to be confirmed with more studies. There is no evidence that visual deficits are common in COPD. The role that precipitating factors such as syncope and postural hypotension may have on fall risk is unclear. Exacerbations and dyspnea do not have a precipitating effect on fall risk but they contribute to the progressive physical deterioration that may theoretically increase the risk for falls. While these results suggest that people with COPD might have an increased susceptibility to fall compared to their healthy peers, further research is needed to determine the prevalence of falls and specific risk factors for falls in people living with COPD.

Effects of Respiratory Muscle Training on Performance in Athletes: A Systematic Review With Meta-analyses

Abstract HajGhanbari, B, Yamabayashi, C, Buna, TR, Coelho, JD, Freedman, KD, Morton, TA, Palmer, SA, Toy, MA, Walsh, C, Sheel, AW, and Reid, WD. Effects of respiratory muscle training on performance in athletes: A systematic review with meta-analysis. J Strength Cond Res 27(6): 1643–1663, 2013—The purpose of this study was to perform a systematic review to determine if respiratory muscle training (RMT) improves sport performance and respiratory muscle strength and endurance. Methodology followed the Cochrane Collaboration protocol. MEDLINE, CINAHL, SPORTDiscus, PEDro, EMBASE, EBM reviews, and COCHRANE electronic databases were searched until July 2011. Articles were included if: (a) participants were athletes; (b) RMT was compared with sham or control in a randomized controlled design and included outcomes of respiratory muscle and sport performance; and (d) published in English. Quality assessment using PEDro and data abstraction was performed by 2 authors. Outcomes evaluated were measures of sport performance, exercise capacity, spirometry, and respiratory muscle strength and endurance. Meta-analyses were performed on outcomes reported in 2 or more papers. Results of this systematic review revealed that of the 6,923 citations retrieved from the search strategy, 21 met the inclusion criteria. Meta-analyses demonstrated a significant positive effect of RMT on sport performance outcomes of time trials, exercise endurance time, and repetitions on Yo-Yo tests. Inspiratory muscle strength and endurance improved in most studies, which in part, was dependent on the type of RMT employed. Determination of the type of athlete that may benefit most from RMT was limited by small sample sizes, differing RMT protocols, and differences in outcome measures across studies. In conclusion, RMT can improve sport performance. Closer attention to matching the ventilatory demands of RMT to those required during athletic competition and more aggressive progression of training intensity may show greater improvements in future studies.

Electrical stimulation and peripheral muscle function in COPD: a systematic review.

BACKGROUND Chronic obstructive pulmonary disease (COPD) can lead to peripheral muscle atrophy and weakness. Electrical stimulation (ES) is commonly used to improve muscle function and structure. The purpose of this systematic review is to determine the effect of ES on muscle function, muscle size, fibre characteristics and exercise performance in patients with COPD. METHODS A search was performed in seven electronic databases (Cochrane Controlled Trials Register, Pubmed, CINAHL, Embase, SPORTDiscus, Web of Science, PEDro). Inclusion criteria were: (1) randomized controlled trials (RCTs), (2) on COPD patients, (3) investigating a defined protocol of ES applied to the lower extremities, (4) analysing at least one main outcome, (5) full text available. Two reviewers extracted the data and evaluated the methodological quality of the studies using the PEDro scale. RESULTS The initial search yielded 167 abstracts, of which five RCTs met the inclusion criteria. The mean (SD) methodological quality of the studies was 6.2+1.3 out of 10. Meta-analyses of three studies showed significant increases in muscle torque and walk distance in the ES groups compared to values in the control, sham or other treatment groups. Measures of muscle size revealed equivocal evidence. Patients with less severe COPD tended to show less improvement. CONCLUSIONS The modest effect sizes after ES, small n, and small number of studies provide weak evidence for the effectiveness of ES to improve lower limb muscle function in COPD patients. Further study should elucidate the optimal parameters for ES protocols and selection criteria for responders and non-responders.

Eccentric Exercise in Patients with Chronic Health Conditions: A Systematic Review

PURPOSE The capacity of eccentric actions to produce muscle hypertrophy, strength gains, and neural adaptations without stressing the cardiopulmonary system has led to the prescription of eccentric training programmes in patients with low tolerance to exercise, such as elders or those with chronic health conditions. The purpose of this systematic review was to analyze the evidence regarding the effectiveness and suitability of eccentric training to restore musculoskeletal function in patients with chronic diseases. SUMMARY OF KEY POINTS Relevant articles were identified from nine databases and from the reference lists of key articles. Articles were assessed to determine level of evidence and scientific rigour. Nine studies met the inclusion criteria. According to Sacketts levels of evidence, 7 studies were graded at level IIb, 1 study at level IV, and the remaining study at level V. Articles were also graded for scientific rigour according to the PEDro scale. One study was rated as high quality, 4 studies were rated as moderate, and 2 studies were graded as poor quality. CONCLUSIONS Eccentric training may be safely used to restore musculoskeletal function in patients with some specific chronic conditions. However, the heterogeneity of diseases makes it very difficult to extrapolate results and to standardize clinical recommendations for adequate implementation of this type of exercise. More studies are needed to establish the potential advantages of eccentric training in chronic conditions.

The effect of heat applied with stretch to increase range of motion: A systematic review

Application of heat to muscle is commonly advocated to enhance the efficacy of stretching. However, the effect of this combined therapy using different methods of heating, applied to different muscles, and after one or multiple treatments, is not known. To perform a systematic review to address the question: Does stretching augmented by heat application result in greater gains in range of motion (ROM) compared to stretch alone? The following databases were searched for original articles that evaluated our question: MEDLINE, EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials, SPORTDiscus and PEDro databases. After title and abstract screening followed by full-text screening, the quality of included articles was assessed and their data was abstracted. Screening, data abstraction and quality assessment was performed and consensus was achieved by two reviewers. Range of motion (ROM) data were synthesized by meta-analyses for overall effect and subgroup analysis according to muscle group, method of heat application, single or multiple treatments, and reported tightness of muscle. Twelve studies were included and reported the effects of stretch with or without heat on ROM of 352 participants. Heat applications included ultrasound, shortwave diathermy and hot packs. Meta-analyses and subgroup analyses demonstrated greater increases in ROM after heat and stretch (H + S) than heat alone. Subgroup analysis of muscle groups and the method of heat application showed some trends, but no significant differences. Multiple treatments (more so than single treatments) showed consistent treatment effects of H + S versus stretch alone amongst subgroups. Muscles described as tight did not show a greater treatment effect in response to H + S compared to muscles not reported as tight. Heating provides an added benefit on stretch related gains of ROM in healthy people.