Exercise Fatiguability in Older Adults: The Protective Effects of Dietary Nitrate Supplementation
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Aging
- Sponsor
- Marquette University
- Enrollment
- 40
- Locations
- 1
- Primary Endpoint
- Change in fatigability of the knee extensor muscles with beetroot juice supplementation
- Last Updated
- 3 years ago
Overview
Brief Summary
Vascular and skeletal muscle function decline with age and are associated with decreased nitric oxide (NO) bioavailability. Dietary nitrate supplementation in the form of beet root juice increases NO bioavailability and improves exercise tolerance in younger adults, yet its effects on fatigability in older adults are largely unknown. The proposed research will investigate the impact of increased NO bioavailability on vascular function, skeletal muscle bioenergetics, and fatigability in older (≥65 yrs) men and women.
Investigators
Timothy Fulton
Principal Investigator
Marquette University
Eligibility Criteria
Inclusion Criteria
- •Healthy men and women ≥ 60 years old
Exclusion Criteria
- •body mass index ≥40 kg/m2;
- •type 1 or type 2 diabetes or HbA1c \>6.5%
- •uncontrolled hypertension;
- •active cancer, cancer in remission, or having received treatment for any form of cancer in the previous five years;
- •coronary artery disease;
- •cardiovascular disease (e.g., PAD, PVD);
- •abnormal and untreated thyroid function;
- •chronic and/or regular nonsteroidal anti-inflammatory drugs (NSAID) consumption,
- •tobacco use (includes smoking);
- •any condition that presents a limitation to exercise (e.g., severe arthritis, COPD, neuromuscular disorder, moderate or severe cognitive impairment, Alzheimer's Disease, severe untreated sleep apnea).
Outcomes
Primary Outcomes
Change in fatigability of the knee extensor muscles with beetroot juice supplementation
Time Frame: Day 8 (after 7 days of placebo supplementation) and day 29 (after 14 days of a washout period with no supplementation plus 7 days of beetroot juice supplementation)
Fatigability will be quantified as the reduction in limb muscle power output during a 4-minute dynamic fatiguing exercise task using a dynamometer. Fatigability after 7 days of beetroot juice supplementation will be compared with fatigability after 7 days of placebo supplementation, with the outcome measure being the change (or difference) between these two supplementation conditions.
Secondary Outcomes
- Change in muscle efficiency with beetroot juice supplementation(Day 8 (after 7 days of placebo supplementation) and day 29 (after 14 days of a washout period with no supplementation plus 7 days of beetroot juice supplementation))
- Change in femoral artery blood flow with beetroot juice supplementation(Day 8 (after 7 days of placebo supplementation) and day 29 (after 14 days of a washout period with no supplementation plus 7 days of beetroot juice supplementation))