Comparison of a Pneumatic Compression Device to a Compression Garment During Recovery from DOMS.

The purpose of this study was to determine the effects of a pneumatic compression device (PCD) compared to a continuously-worn compression sleeve (CS) during a five-day recovery period from delayed-onset muscle soreness (DOMS) of the elbow flexors. Eight college-aged students participated in this crossover design study. The muscle-damage protocol consisted of four sets of 25 repetitions of isokinetic concentric elbow flexion followed by eccentric elbow extension at 60°/second. Immediately following the muscle-damage protocol, subjects either wore a CS continually for five days or completed daily, 20-minute PCD treatments for five days. Swelling, range of motion (ROM), and pain were measured daily during the five-day recovery period. Subjects rested for seven additional days before completing another muscle-damage protocol and the remaining treatment. Treatment order was randomized and balanced. Muscle swelling, assessed via changes in upper arm circumference, was significantly lower in the PCD treatment (1.7 vs. 2.0 cm in CS, p = 0.012), however there was no difference in lower arm circumference (p = 0.091). ROM disturbances during the PCD treatment were lower (mean peak reduction in ROM -9.04 degrees in PCD compared to -17.25 degrees in CS, p < 0.05) and peak pain was lower by 39% (27.5 mm in PCD compared to 45.2 mm in CS, p < 0.05) when compared to the CS treatment. These findings suggest that daily treatments using a PCD further reduce peak disturbance and recovery time from DOMS of the elbow flexors when compared to a continuously-worn CS.

The prevalence of cardiovascular disease risk factors and obesity in firefighters.

Obesity is associated with increased risk of cardiovascular disease (CVD) mortality. CVD is the leading cause of duty-related death among firefighters, and the prevalence of obesity is a growing concern in the Fire Service. Methods. Traditional CVD risk factors, novel measures of cardiovascular health and a measurement of CVD were described and compared between nonobese and obese career firefighters who volunteered to participate in this cross-sectional study. Results. In the group of 116 men (mean age 43 ± 8 yrs), the prevalence of obesity was 51.7%. There were no differences among traditional CVD risk factors or the coronary artery calcium (CAC) score (criterion measure) between obese and nonobese men. However, significant differences in novel markers, including CRP, subendocardial viability ratio, and the ejection duration index, were detected. Conclusions. No differences in the prevalence of traditional CVD risk factors between obese and nonobese men were found. Additionally, CAC was similar between groups. However, there were differences in several novel risk factors, which warrant further investigation. Improved CVD risk identification among firefighters has important implications for both individual health and public safety.

Use of salivary osmolality to assess dehydration.

OBJECTIVE: To investigate the ability of salivary osmolality to assess dehydration while subjects perform alternating work/rest cycles in personal protective equipment (PPE). METHODS: Eight healthy men (mean ± standard deviation age: 23.5 ± 4.9 years; body fat: 17.8% ± 5.0%; maximum volume of oxygen consumption [VO(2max)]: 57.2 ± 5.5 mL·kg(-1)·min(-1)) performed two exercise trials: one while wearing shorts and a T-shirt (EX) and one while wearing firefighting PPE (EX+PPE). Saliva samples were taken before exercise, at minutes 40, 80, and 120 of the exercise trial, and during recovery. RESULTS: Percent body mass loss (BML) was significantly greater while the subjects were wearing PPE (2.18% ± 0.54% vs. control 0.81% ± 0.30%). Salivary osmolality increased significantly in both trials (73.4 ± 12.4 to 125.1 ± 30.3 mOsm·kg(-1) and 70.1 ± 12.5 to 83.6 ± 17.7 mOsm·kg(-1)); however, the increase in the EX+PPE trial was significantly greater than the increase in the EX trial. Plasma osmolality did not change significantly in either trial, whereas urinary osmolality increased significantly in both trials. Changes in salivary osmolality were strongly correlated with percent BML (r = 0.80; p < 0.01). CONCLUSION: Salivary osmolality may be a sensitive indicator of moderate dehydration under carefully controlled conditions.

Moderate static stretching and torque production of the knee flexors.

Recent studies have suggested that acute static stretching (SS) decreases muscular strength and performance, particularly of the knee extensors. The purpose of this study was to investigate the effect of SS on peak concentric and eccentric torque production in the knee flexors. Subjects (13 women and 16 men) were tested for isokinetic concentric (CON) and eccentric (ECC) peak torque at 2 velocities (60 and 210 degrees x s(-1)) before and after a 3-minute knee flexor SS protocol. Subjects also underwent a control day in which the isokinetic pre- and posttests were separated by 10 minutes of sitting rather than stretching. A sit and reach test was administered on both days to assess changes in flexibility that occurred as a result of the stretching or control protocols. The change in flexibility was significantly greater after stretching than after sitting. Changes in peak torque were not significantly different between the stretching and control conditions for either velocity or contraction type. Compared with the control condition, SS of the knee flexors before maximal isokinetic testing does not lead to significantly diminished CON or ECC torque output at slow or fast contraction velocities. These data suggest that moderate SS does not impact the performance of all muscle groups.