Heat Therapy for Prediabetes

(HEAT Trial)

Overseen By Danielle Levitt, PhD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Hui Ying Luk

Must not be taking: Corticosteroids, Opiates, Benzodiazepines, others

Disqualifiers: Peripheral neuropathies, Blood thinners, Cardiovascular impairments, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 48

54 Participants Needed

Trial Summary

What is the purpose of this trial?

The main goal of this two-phase clinical trial is to learn whether local heat therapy, using heat pads applied to the legs, can enhance skeletal muscle health, physical function, and blood sugar control in a manner comparable to exercise, specifically High-Intensity Interval Training (HIIT), in older individuals with prediabetes. The study aims to answer the following questions: 1. Does local heat therapy improve muscle architecture (e.g., muscle cross-sectional area, capillary density, mitochondrial content), glucose tolerance, and frailty indicators similarly to HIIT in older individuals with prediabetes? 2. Does local heat therapy as a pre-conditioning method enhance the skeletal muscle response to HIIT in older individuals with prediabetes?

Will I have to stop taking my current medications?

Yes, you will need to stop taking certain medications that could interfere with the study, such as corticosteroids, opiates, benzodiazepines, tricyclic antidepressants, beta blockers, sulfonylureas, insulin, metformin, anticoagulants, barbiturates, insulin sensitizers, and fibrates.

What data supports the effectiveness of the treatment Heat Therapy for Prediabetes?

Research shows that heat therapy, like using saunas or hot tubs, can improve insulin sensitivity and help control blood sugar levels, similar to the benefits of exercise. This suggests it might be helpful for managing prediabetes. ^{1 2 3 4 5}

Is heat therapy safe for humans?

Heat therapy, including saunas and hot baths, has been used safely for various conditions like diabetes and cardiovascular diseases. It may help improve blood sugar control and reduce blood pressure, similar to the benefits of exercise, and is generally well-tolerated by people. ^{1 2 3 4 6}

How is heat therapy for prediabetes different from other treatments?

Heat therapy, like hot baths or saunas, is unique because it can improve insulin sensitivity and cardiovascular health without the need for physical exercise, making it a good option for those who cannot engage in regular physical activity. It works by boosting the body's heat shock proteins, which can help manage blood sugar levels and improve heart health, similar to the effects of exercise. ^{1 2 3 5 7}

Research Team

Hui-Ying Luk, PhD; Danielle Levitt, PhD

Principal Investigator

Texas Tech University

Eligibility Criteria

The HEAT trial is for older individuals who have prediabetes. It's designed to see if applying heat pads to the legs can improve muscle health and blood sugar control, similar to high-intensity exercise.

Inclusion Criteria

Sedentary (structured exercise <30 minutes, 3x/week)

I am 60 years old or older.

I drink less than 8 (if woman) or 15 (if man) alcoholic drinks per week.

Exclusion Criteria

I have a history of nerve damage in my hands or feet.

Currently pregnant

I am currently on prescription blood thinners.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Phase 1: Local Heat Therapy or HIIT

Participants in the Local Heat Therapy group use heat pads on both thighs for 90 minutes daily, 7 days a week for 12 weeks. Participants in the HIIT group perform high-intensity interval training 3 days a week for 12 weeks.

12 weeks

12 laboratory visits for LHT group, 36 visits for HIIT group

Phase 2: High-Intensity Interval Training

All participants perform high-intensity interval training 3 days a week for 12 weeks.

12 weeks

36 laboratory visits

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Heat Therapy
• High-intensity interval training

Trial Overview This study tests whether leg heat therapy can match or boost the benefits of High-Intensity Interval Training (HIIT) on muscle structure, glucose tolerance, and frailty in older adults with prediabetes.

Participant Groups

Group I: Local Heat Therapy Experimental Treatment 2 Interventions

Phase 1: Heat pads will be applied to both legs and set to a pre-determined, optimized temperature to raise the intramuscular temperature to \~40°C. Each heating session will last for 90 min/d, 7d/wk (6 at-home and 1 in-lab) for 12 wks. Phase 2: High-intensity interval training will be performed 3 d/wk for 12 wks. Each exercise session will consist of 4 cycling exercise intervals at 90-95% HRpeak for 4 min with 3 min active rest.

Group II: High-Intensity Interval Training Active Control 1 Intervention

Phase 1: High-intensity interval training will be performed 3 d/wk for 12 wks. Each exercise session will consist of 4 cycling exercise intervals at 90-95% HRpeak for 4 min with 3 min active rest. Phase 2: N/A

Group III: Thermoneutral Therapy Placebo Group 2 Interventions

Phase 1: Heat pads will be applied to both legs and set to a pre-determined temperature to keep the intramuscular temperature in a thermoneutral state (\~35-37°C). Each heating session will last for 90 min, 7d/wk (6 at-home and 1 in-lab) for 12 weeks. Phase 2: High-intensity interval training will be performed 3 d/wk for 12 wks. Each exercise session will consist of 4 cycling exercise intervals at 90-95% HRpeak for 4 min with 3 min active rest.

Who Is Running the Clinical Trial?

Hui Ying Luk

Lead Sponsor

Trials

1

Recruited

50+

Texas Tech University

Lead Sponsor

Trials

89

Recruited

10,300+

Findings from Research

Heat therapy, such as sauna and hot tub use, has been shown to significantly reduce key diabetes markers, including a 1% reduction in glycated hemoglobin, making it a promising treatment option for type 2 diabetes.

Mechanistically, heat therapy may improve insulin sensitivity and reduce body weight through increased levels of nitric oxide and heat shock protein 70, suggesting a biological basis for its benefits in metabolic health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Heat shock proteins and heat therapy for type 2 diabetes: pros and cons. Krause, M., Ludwig, MS., Heck, TG., et al.[2022]

Long-term hot-tub therapy (HTT) for 5 months significantly improved various health markers in diabetic rats, including lipid profiles, antioxidant capacity, and insulin secretion, while also reducing advanced glycation end products (AGEs).

The increase in extracellular heat shock protein (Hsp70) levels due to HTT may help protect proteins from damage, suggesting a potential mechanism for the observed benefits in managing diabetic complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of hot-tub therapy on serum Hsp70 level and its benefit on diabetic rats: a preliminary report. Bathaie, SZ., Jafarnejad, A., Hosseinkhani, S., et al.[2022]

Regular thermal therapy, such as using saunas or hot baths, can improve insulin sensitivity and enhance nitric oxide production, which are beneficial for vascular health, similar to the effects of aerobic exercise.

Thermal therapy may serve as a practical alternative for individuals unable to engage in regular exercise, potentially aiding in diabetic control and lowering blood pressure in conditions like hypertension and heart failure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Regular thermal therapy may promote insulin sensitivity while boosting expression of endothelial nitric oxide synthase--effects comparable to those of exercise training. McCarty, MF., Barroso-Aranda, J., Contreras, F.[2009]

A 12-week study involving 32 prediabetic male patients showed that high-intensity interval training (HIIT) significantly reduced blood glucose levels compared to continuous endurance training at anaerobic threshold (CETAT).

Both HIIT and continuous endurance training at maximal fat oxidation (CETFAT) improved insulin resistance indices similarly, indicating that exercise intensity and type can effectively influence hormonal changes in prediabetic individuals.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

High-Intensity Interval vs. Continuous Endurance Training: Preventive Effects on Hormonal Changes and Physiological Adaptations in Prediabetes Patients. Safarimosavi, S., Mohebbi, H., Rohani, H.[2022]

In a pilot study involving 45 outpatients with moderate depression, hyperthermic baths (HTB) showed a significant reduction in depression severity after 2 weeks, with a mean improvement of 4.3 points on the Hamilton Depression Rating Scale compared to a physical exercise program.

HTB was well-tolerated with no serious adverse events reported, making it a promising and accessible add-on treatment for depression, especially for individuals who may struggle with traditional exercise.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects and feasibility of hyperthermic baths in comparison to exercise as add-on treatment to usual care in depression: a randomised, controlled pilot study. Naumann, J., Kruza, I., Denkel, L., et al.[2021]

High-Intensity Interval Training (HIIT) significantly improves glycaemic control, aerobic resistance, and body composition in individuals with type 2 diabetes, based on a meta-analysis of 180 studies involving participants aged 18 and older.

Specific types of HIIT, such as Sprint Interval HIIT (SIT-HIIT) and Short Interval HIIT (SI-HIIT), may offer greater benefits for fasting blood glucose levels compared to traditional continuous aerobic training.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of chronic high-intensity interval training programs on glycaemic control, aerobic resistance, and body composition in type 2 diabetic patients: a meta-analysis. Arrieta-Leandro, MC., Moncada-Jiménez, J., Morales-Scholz, MG., et al.[2023]

References

1. England pubmed.ncbi.nlm.nih.gov

Heat shock proteins and heat therapy for type 2 diabetes: pros and cons. [2022]

2. England pubmed.ncbi.nlm.nih.gov

The effect of hot-tub therapy on serum Hsp70 level and its benefit on diabetic rats: a preliminary report. [2022]

3. United States pubmed.ncbi.nlm.nih.gov

Regular thermal therapy may promote insulin sensitivity while boosting expression of endothelial nitric oxide synthase--effects comparable to those of exercise training. [2009]

4. United States pubmed.ncbi.nlm.nih.gov

High-Intensity Interval vs. Continuous Endurance Training: Preventive Effects on Hormonal Changes and Physiological Adaptations in Prediabetes Patients. [2022]

5. Canada pubmed.ncbi.nlm.nih.gov

Habitual Hot-Tub Bathing and Cardiovascular Risk Factors in Patients With Type 2 Diabetes Mellitus: A Cross-Sectional Study. [2022]

6. England pubmed.ncbi.nlm.nih.gov

Effects and feasibility of hyperthermic baths in comparison to exercise as add-on treatment to usual care in depression: a randomised, controlled pilot study. [2021]

7. Italy pubmed.ncbi.nlm.nih.gov

The effect of chronic high-intensity interval training programs on glycaemic control, aerobic resistance, and body composition in type 2 diabetic patients: a meta-analysis. [2023]