Caron MA, Debigaré R, Dekhuijzen PN, Maltais F. Comparative assessment of the quadriceps and the diaphragm in patients with COPD. J Appl Physiol 107: 952–961, 2009. First published April 9, 2009; doi:10.1152/japplphysiol.00194.2009.— Chronic obstructive pulmonary disease (COPD) and other chronic diseases such as heart failure are accompanied by skeletal muscle alterations that further enhance m...

BACKGROUND Although muscle strength and mass are highly correlated, the relationship between direct measures of low muscle mass (sarcopenia) and strength in association with mortality has not been examined. METHODS Total mortality rates were examined in the Health, Aging and Body Composition (Health ABC) Study in 2292 participants (aged 70-79 years, 51.6% women, and 38.8% black). Knee extensi...

OBJECTIVE To compare the efficacy of posterolateral hip muscle strengthening versus quadriceps strengthening in reducing pain and improving health status in persons with patellofemoral pain (PFP). DESIGN Comparative control trial. SETTING Rehabilitation facility. PARTICIPANTS Persons with a diagnosis of PFP (N=36; 18 men, 18 women). INTERVENTIONS Patients were alternately assigned to a ...

STUDY DESIGN A case series. OBJECTIVES The purpose of this case series was to assess the effect of high-intensity neuromuscular electrical stimulation (NMES) on quadriceps strength and voluntary activation following total knee arthroplasty (TKA). BACKGROUND Following TKA, patients exhibit long-term weakness of the quadriceps and diminished functional capacity compared to age-matched healthy...

STUDY DESIGN Case report. BACKGROUND Following total knee arthroplasty (TKA), restoration of normal quadriceps muscle function is rare. One month after surgery, quadriceps torque (force) is only 40% of preoperative values and quadriceps activation is only 82% of preoperative levels, despite initiating postoperative rehabilitation the day after surgery. Early application of neuromuscular elect...

Mitochondrial muscle alterations are common in patients with chronic obstructive pulmonary disease (COPD) and manifest mainly as decreased oxidative capacity and excessive production of reactive oxygen species (ROS). The significant loss of oxidative capacity observed in the quadriceps of COPD patients is mainly due to reduced mitochondrial content in the fibers, a finding consistent with the c...

AIM To determine whether muscle function is compromised in healthy smokers in comparison with activity-matched non-smokers. METHODS Nine male smokers (aged 22.2 +/- 2.5 years: mean +/- SD) with a smoking history of 2.5 +/- 3.1 pack years, and ten male control participants (25.4 +/- 2.9 years) matched for physical activity level participated in this study. Knee extensor strength was measured u...

Objectives: The purpose of this study was to investigate the contributions of functional and morphological factors in the recovery of the quadriceps muscle after anterior cruciate ligament (ACL) reconstruction. Methods: Nine subjects (31.3±5.8 years) underwent eccentric exercise sessions twice a week for 12 weeks. Quadriceps muscle function was evaluated using an isokinetic dynamometer (isometr...

The purpose of this study was to examine the effects of HBO2 therapy on exercise-induced muscle soreness. Subjects (n = 6 male and 10 female university student volunteers) were randomly divided into an experimental group that received HBO2 therapy and a control group that did not receive any treatments. HBO2 treatments consisted of 5 sessions of breathing 95% oxygen at 2.5 atm abs for 100 min. ...

The purpose was to study the effects on muscle function of an electrical stimulation bout applied unilaterally on thigh muscles in healthy male volunteers. One group (ES group, n = 10) received consecutively 100 isometric contractions of quadriceps and 100 isometric contractions of hamstrings (on-off ratio 6-6 s) induced by neuromuscular electrical stimulations (NMES). Changes in muscle torque,...