This study investigates the effects of two weeks of reduced daily ambulation and a subsequent return to normal physical activity on metabolic health of older adults.

Aging results in a progressive loss of muscle mass that is accelerated by periods of muscular disuse, common for older adults during hospitalization or convalescence from illness. Transient physical inactivity has been shown to cause muscular atrophy and impairments in insulin sensitivity in both younger and older adults. However, the recovery capacity of older adults after such physical inactivity remains unknown. This study aims to determine the impact of two weeks of daily step reduction to ≤1000 steps per day, an experimental model mimicking short-term physical inactivity, on glycemic control in older adults and further investigate whether older adults are able to recover from the consequences of this inactivity simply by returning to their habitual activity for 14 days.

Inclusion Criteria:

• Non-smoker

Exclusion Criteria:

• Use of assistive walking devices
• Chronic use of analgesic or anti-inflammatory drugs
• History of neuromuscular problems or muscle and/or bone wasting disease
• Acute or chronic illness including cardiac, pulmonary, liver or kidney abnormalities, uncontrolled hypertension, insulin or non-insulin dependent diabetes or other metabolic disorders
• Daily use of statins, particularly simvastatin and atorvastatin
• Use of medications known to affect protein metabolism
• Normally complete fewer than 3000 steps per day