Concurrent cardiovascular and resistance training in healthy older adults.

PURPOSE: The recommendations for exercise training and physical activity for older adults include cardiovascular and resistance training components (CVT and RT, respectively). The purpose of the present investigation was to compare the fitness benefits of concurrent CVT and RT with those attained through an equivalent duration of CVT or RT alone. METHODS: Thirty-six participants (ages 60-84) were assigned to a control group or to one of three exercise treatment groups. The treatment groups exercised three times per week for 12 wk using RT (N = 11), CVT (N = 10), or CVT and RT (BOTH, N = 9). Pre- and post-training, participants performed a submaximal exercise test (GXT), five repetition-maximum strength tests (5RM), and the AAHPERD functional fitness test for older adults. RESULTS: All exercise treatment groups revealed lower resting heart rate and rate-pressure product; lower exercise diastolic blood pressure and rating of perceived exertion; increased GXT duration; increased leg, back, and shoulder 5RM scores; and improved AAHPERD flexibility, coordination, and cardiovascular endurance scores. The exercise treatment groups responded differently on the following: RT and BOTH enhanced arm and chest strength more than CVT; and BOTH enhanced AAHPERD strength and agility scores more than CVT or RT. CONCLUSIONS: Concurrent CVT and RT is as effective in eliciting improvements in cardiovascular fitness and 5RM performance as CVT or RT, respectively. Moreover, incorporating both CVT and RT in exercise programs for older adults may be more effective in optimizing aspects of functional fitness than programs that involve only one component.

Hypochlorous acid inhibits Ca(2+)-ATPase from skeletal muscle sarcoplasmic reticulum.

Hypochlorous acid (HOCl) is produced by polymorphonuclear leukocytes that migrate and adhere to endothelial cells as part of the inflammatory response to tissue injury. HOCl is an extremely toxic oxidant that can react with a variety of cellular components, and concentrations reaching 200 microM have been reported in some tissues. In this study, we show that HOCl interacts with the skeletal sarcoplasmic reticulum Ca(2+)-adenosinetriphosphatase (ATPase), inhibiting transport function, HOCl inhibits sarcoplasmic reticulum Ca(2+)-ATPase activity in a concentration-dependent manner with a concentration required to inhibit ATPase activity by 50% of 170 microM and with complete inhibition of activity at 3 mM. A concomitant reduction in free sulfhydryl groups after HOCl treatment was observed, paralleling the inhibition of ATPase activity. It was also observed that HOCl inhibited the binding of the fluorescent probe fluorescein isothiocyanate to the ATPase protein, indicating some structural damage may have occurred. These findings suggest that the reactive oxygen species HOCl inhibits ATPase activity via a modification of sulfhydryl groups on the protein, supporting the contention that reactive oxygen species disrupt the normal Ca(2+)-handling kinetics in muscle cells.

A primer of current molecular genetic strategies for clinicians.

For the clinician to take full advantage of the rapid advances in molecular medicine, a working knowledge of the recombinant DNA methodologies employed will be required. This primer introduces current cloning strategies by examination of the cloning of the cystic fibrosis gene, an opioid receptor, and olfactory receptors that used the methodologies of DNA linkage analysis, functional cloning, and polymerase chain reaction with degenerate oligonucleotide primers, respectively. Molecular information obtained after cloning has had immediate effects on diagnosis and genetic counseling and holds the promise of novel treatment strategies, including somatic gene therapy.