About this trial
This study aims to determine the effects of \~12 weeks of repeated hot water immersion ("heat therapy") vs. thermoneutral water immersion on blood pressure and vascular function in late middle-life to older (≥40 years) adults. The study also aims to determine the effects of \~12 weeks of heat therapy on fluid cognitive and cerebrovascular function.
Eligibility criteria
Qualifiers
Able to provide informed consent (no clinical diagnosis of dementia or related diseases AND mini mental state exam score >20).
Willing to accept random assignment to intervention.
Aged 40+ years.
Premenopausal women must not be pregnant (confirmed by urine pregnancy test).
Disqualifiers
Individuals taking 3+ anti-hypertensive medications (rationale: these individuals typically have resistant or secondary hypertension. Individuals taking 1-2 anti-hypertensive medications will still be included, with the exception of beta-blockers.)
SBP 140-159 mmHg but not on anti-hypertensive medications. (rationale: ACC/AHA guidelines indicate that immediate pharmacotherapy is advised for these individuals. Potential subjects with SBP in this range will discuss options/receive recommendations from a CTRC physician and be referred to their primary care provider. If they begin anti-hypertensive medication, they will be eligible to participate in the study after they have been on them for at least 3 months, assuming they still qualify. If they decide not to begin anti-hypertensive medications, they must receive approval for their primary care provider that it is ok for them to participate in the study.)
Regular vigorous aerobic/endurance exercise: >4 bouts per week for >30 min per bout at a workload of >10 METS, determined based on screening surveys and workload confirmed by MAQ during Visit 1. (rationale: aerobic exercise training independently lowers blood pressure and improves arterial function33,74,75).
Body mass index (BMI) >40 kg/m2 (rationale: BP and vascular measurements can be inaccurate in severely obese subjects and these subjects may differ in many ways from normal weight, overweight, or less obese subjects).
Trial design
Treatments tested in this trial
- Heat therapy
- Thermoneutral water immersion