Affiliations: [a] Department of Sport and Physical Activity, Bournemouth University, Poole, Dorset, UK | [b] Orthopaedic Research Institute, Bournemouth University, Bournemouth, Dorset, UK
Correspondence:
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Corresponding author: James P. Gavin, Department of Sport and Physical Activity, Bournemouth University, Fern Barrow, Poole BH12 5BB, Dorset, UK. Tel.: +44 0 1202 566303; Fax: +44 0 1202 962736; E-mail: jgavin@bournemouth.ac.uk.
Abstract: OBJECTIVE: To compare EMG activity of the hip and thigh muscles during traditional static bed exercises and the sit-to-stand exercise in healthy older adults. METHODS: Twenty-four healthy, older adults (8 males; age 65 ± 7 y) performed four static rehabilitation exercises: isometric contractions of the gluteal, abductor, inner quadriceps and quadriceps (ten, ∼ 5 s submaximal contractions, with 60 rests), and the sit-to-stand test. Electromyographic (EMG) activity was recorded from the rectus femoris, vastus medialis, gluteus medius, biceps femoris and gluteus maximus, and root mean square-processed (RMS) in this observational preliminary study. Handgrip strength and 10 m walking speed represented participant characteristics. RESULTS: Hip and thigh muscles were activated differently between the isometric bed and sit-to-stand exercises. Greatest RMS activity was shown in the chair rising phase of the sit-to-stand exercise. No bed exercise exceeded the muscle RMS activity required to perform a sit-to-stand, and only for sit-to-stands were all muscles activated over 40% of maximal; the level required to stimulate muscle strength adaptation. CONCLUSIONS: Functional daily activities, such as sit-to-standing, produce greater muscle activity than static bed exercises in healthy older adults. Sit-to-stands should be included in exercise and rehabilitation programs for older adults to evoke sufficient levels of neuromuscular activation for muscle strength adaptation.
