Cold-Water Immersion for Heat Stress in Older Adults

Overseen By Rachel Cottle, MS

Age: 65+

Sex: Any

Trial Phase: Academic

Sponsor: Penn State University

Must not be taking: Antiepileptics, Methotrexate

Disqualifiers: Chron's, Diverticulitis, Tobacco, others

Compensation: Varies

Number of Visits: 5

Duration: 6-7 weeks

20 Participants Needed

Trial Summary

What is the purpose of this trial?

The earth's climate is warming, and the number of heat waves has increased in recent years. At the same time, the number of adults over the age of 65 is growing. Humans sweat and increase blood flow to the skin to cool their body when they get hot. Older adults do not do this as well as young adults. This makes it harder to safely be in warm and/or humid conditions. It is important to learn about cooling strategies for older adults to safely be in warm and/or humid conditions. There is compelling evidence that intermittent hand and forearm cold-water immersion effectively reduces the rise of core temperature during heat stress in older adults. However, it is still unknown if this is an effective cooling strategy for older adults. Furthermore, our laboratory has shown that folic acid supplementation improves blood flow responses in older adults. This may be beneficial to older adults during heat stress.

Will I have to stop taking my current medications?

The trial requires that you do not take antiepileptic or antiseizure medications, or methotrexate. If you are on these medications, you would need to stop taking them to participate.

What data supports the effectiveness of the treatment Intermittent cold-water hand and forearm immersion for heat stress in older adults?

Research shows that immersing hands and forearms in cold water can help reduce body temperature and heart rate, making people feel more comfortable in hot conditions. This method has been effective in improving exercise performance in the heat and extending work time by reducing heat stress. ^{1 2 3 4 5}

Is cold-water immersion of the hand and forearm safe for humans?

Cold-water immersion of the hand and forearm appears to be generally safe for humans, as studies have shown it can improve exercise performance and reduce heat stress without significant adverse effects. However, some discomfort or pain may occur, especially if the water is very cold or if hands are immersed without protective gloves. ^{1 4 6 7 8}

How does the treatment of intermittent cold-water hand and forearm immersion for heat stress in older adults differ from other treatments?

This treatment is unique because it involves immersing the hands and forearms in cold water to reduce body temperature and alleviate heat stress, which is different from other methods that might focus on whole-body cooling or medication. It specifically targets peripheral cooling, which can effectively lower core and skin temperatures, improve comfort, and enhance performance in hot conditions. ^{1 2 4 9 10}

Research Team

W. Larry Kenney, Ph.D.

Principal Investigator

The Pennsylvania State University

Eligibility Criteria

This trial is for older adults who may struggle with body cooling due to aging. It's designed to test if dipping hands and forearms in cold water intermittently can help them stay cool in warm conditions.

Inclusion Criteria

English proficiency

I am 65 years old or older.

Exclusion Criteria

Tobacco use

I am currently taking Methotrexate.

I have a history of Crohn's disease or similar bowel conditions.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Treatment

Participants undergo 4 experimental trials, 2 with folic acid supplementation and 2 with placebo, with intermittent hand and forearm cold-water immersion

6-7 weeks

4 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Intermittent cold-water hand and forearm immersion

Trial Overview The study tests a potential cooling method involving intermittent cold-water hand and forearm immersion compared to not using this strategy at all, aiming to see if it helps manage core temperature during heat stress.

Participant Groups

Group I: Folic acid supplementation Experimental Treatment 2 Interventions

5 mg/day folic acid for 6-7 weeks

Group II: Control Placebo Group 2 Interventions

Cellulose placebo tablet for 6-7 weeks

Who Is Running the Clinical Trial?

Penn State University

Lead Sponsor

Trials

380

Recruited

131,000+

Findings from Research

Cold water immersion of the hands and forearms during half-time significantly improved intermittent cycling performance in the heat, with participants showing greater power output in the second half compared to those who rested.

This cooling method also effectively reduced body temperature and heart rate, leading to a more comfortable thermal sensation, which suggests it can enhance exercise performance and comfort in hot conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cold water immersion of the hand and forearm during half-time improves intermittent exercise performance in the heat. Iwahashi, M., Chaen, Y., Yanaoka, T., et al.[2023]

Hand immersion in cool water (25°C and 10°C) significantly reduced core and skin temperatures in men wearing impermeable NBC clothing, compared to no immersion, during rest periods in a warm environment (30°C).

This technique extended the total work time of subjects by 10-20 minutes, suggesting that hand immersion can effectively reduce heat stress when normal heat loss methods are limited.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of hand immersion on body temperature when wearing impermeable clothing. Allsopp, AJ., Poole, KA.[2008]

Maximal voluntary grip strength (MVGS) significantly decreased by 16% after immersing the hand and 13% after immersing the forearm in cold water (5 degrees C), with most reductions occurring in the first 2 minutes.

Wearing a protective glove after unprotected hand cooling also led to a significant 14% reduction in MVGS, indicating that both hand and forearm protection are crucial for maintaining grip strength after cold exposure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effects of cold immersion and hand protection on grip strength. Vincent, MJ., Tipton, MJ.[2008]

Cold-stress tests, particularly using a 10°C water immersion for 10 minutes, have been widely accepted in Japan for diagnosing hand-arm vibration syndrome, focusing on measuring finger-skin temperature.

There is a need for standardization of the cold-stress test methods and environmental factors to improve the reliability and diagnostic significance of the results in epidemiological studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A minireview of studies conducted in japan using finger-skin temperature during cold-stress tests for the diagnosis of hand-arm vibration syndrome. Harada, N., Yoshimura, M., Laskar, MS.[2019]

Cold water immersion (CWI) at temperatures of 10-15°C for 5-15 minutes is shown to effectively enhance recovery of performance in athletes, making it a popular choice for minimizing fatigue after exercise.

Contrast water therapy (CWT), which alternates between cold and hot water, may also aid recovery, but its effectiveness depends on equal time spent in both temperatures and short immersion durations, with no clear dose-response relationship established.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Water immersion recovery for athletes: effect on exercise performance and practical recommendations. Versey, NG., Halson, SL., Dawson, BT.[2022]

In a study involving six subjects, immersion of the forearm in 15°C water for 3 hours revealed cyclic fluctuations in muscle temperature, with the first increase occurring after 75 minutes and averaging a cycle duration of 36 minutes.

The maximum muscle temperature increase ranged from 0.4°C to 1.0°C and was linked to the forearm's circumference, suggesting that muscle blood vessels play a significant role in cold-induced vasodilation, while skin temperature and heat loss remained unchanged.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cyclic intramuscular temperature fluctuations in the human forearm during cold-water immersion. Ducharme, MB., VanHelder, WP., Radomski, MW.[2019]

Cold-stress tests, which measure finger skin temperature, are important for diagnosing vascular disorders related to hand-arm vibration syndrome, but there is significant variability in test conditions across different studies.

Standardization efforts are needed, as factors like water temperature (ranging from 0 to 15 degrees C), immersion time (0.5 to 20 minutes), and environmental conditions can greatly affect the diagnostic value of these tests, with a preference for higher water temperatures and shorter immersion times to reduce patient discomfort.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cold-stress tests involving finger skin temperature measurement for evaluation of vascular disorders in hand-arm vibration syndrome: review of the literature. Harada, N.[2019]

Using natural rubber gloves during cold water immersion significantly increased finger skin temperature and reduced hand pain compared to bare hands and polyethylene gloves, indicating better thermal protection.

Polyethylene gloves also provided some benefit by reducing pain compared to bare hands, suggesting they can be a suitable alternative for minimizing discomfort during immersion tests.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Influence of waterproof covering on finger skin temperature and hand pain during immersion test for diagnosing hand-arm vibration syndrome. Suizu, K., Inoue, M., Fujimura, T., et al.[2019]

In a study involving 17 male volunteers from different ethnic backgrounds, localized cold stress from foot immersion in 10°C water caused an immediate drop in finger temperature across all groups, but recovery rates varied significantly.

Inuit subjects showed the fastest recovery of finger temperature after cold exposure, while Caucasians and Orientals had slower recovery rates, indicating potential differences in cold tolerance among ethnic groups.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of a local cold stress on peripheral temperatures of Inuit, Oriental, and Caucasian subjects. Livingstone, SD., Grayson, J., Reed, LD., et al.[2022]

Hand immersion in cold water significantly reduces physiological strain during exercise in hot conditions, as shown by a study with 17 heat-acclimated subjects wearing protective garments, where it lowered average rectal temperature by nearly 0.5 degrees Celsius during rest periods.

This method also improved overall tolerance to heat stress, allowing all participants to complete the exercise session with hand immersion, compared to only 12 out of 17 in the control group, indicating it is a practical and effective strategy for enhancing performance in extreme conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Hand immersion in cold water alleviating physiological strain and increasing tolerance to uncompensable heat stress. Khomenok, GA., Hadid, A., Preiss-Bloom, O., et al.[2021]

References

1. Switzerland pubmed.ncbi.nlm.nih.gov

Cold water immersion of the hand and forearm during half-time improves intermittent exercise performance in the heat. [2023]

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

The effect of hand immersion on body temperature when wearing impermeable clothing. [2008]

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

The effects of cold immersion and hand protection on grip strength. [2008]

4. Germany pubmed.ncbi.nlm.nih.gov

A minireview of studies conducted in japan using finger-skin temperature during cold-stress tests for the diagnosis of hand-arm vibration syndrome. [2019]

5. New Zealand pubmed.ncbi.nlm.nih.gov

Water immersion recovery for athletes: effect on exercise performance and practical recommendations. [2022]

6. Germany pubmed.ncbi.nlm.nih.gov

Cyclic intramuscular temperature fluctuations in the human forearm during cold-water immersion. [2019]

7. Germany pubmed.ncbi.nlm.nih.gov

Cold-stress tests involving finger skin temperature measurement for evaluation of vascular disorders in hand-arm vibration syndrome: review of the literature. [2019]

8. Japan pubmed.ncbi.nlm.nih.gov

Influence of waterproof covering on finger skin temperature and hand pain during immersion test for diagnosing hand-arm vibration syndrome. [2019]

9. Canada pubmed.ncbi.nlm.nih.gov

Effect of a local cold stress on peripheral temperatures of Inuit, Oriental, and Caucasian subjects. [2022]

10. Germany pubmed.ncbi.nlm.nih.gov

Hand immersion in cold water alleviating physiological strain and increasing tolerance to uncompensable heat stress. [2021]