“Put a hot pack on it.” It’s common advice for aches and pains. But does heat therapy really work? Here’s what the science says:
Heat Therapy for Pain
Does heat reduce pain?
Sometimes.
Heat therapy via hot packs or hot tubs offers short term pain relief for conditions like muscle soreness, muscle tightness, and myofascial pain.
Heat increases blood flow to the target region, which can promote healing. It also relaxes tense, sore muscles which can offer pain relief.
Heat won’t top the list of best physical therapy treatments anytime soon, but it can be a useful tool to ease musculoskeletal pain, improve sleep, and reduce the need for medication.
Heat for Recovery
Delayed Onset Muscle Soreness (DOMS) is a painful reality for athletes and active adults striving to improve their fitness.
And frankly, it’s the most unpleasant part of building strength.
A few modalities can help:
Ice baths and NSAIDs (like ibuprofen) definitely reduce DOMS. But they also kill your gains.
These 2 anti-inflammatory interventions slow the body’s natural inflammatory process which is essential to make you bigger, faster, and stronger after hard training.
Fortunately, there are better options. Active recovery (i.e. light movement), foam rolling, percussion therapy and heat therapy all reduce DOMS without hampering your body’s adaptation to training.
Applying heat shortly after training can ease muscle soreness for the next 1-3 days.
Heat Therapy for Health
Intentional heat and cold exposure have gotten a lot of attention lately. A previous newsletter explored the pros and cons of ice baths.
But this is the first time we’ve discussed using heat – specifically sauna exposure – for health benefits.
In summary, sauna use is linked with better health.
Research shows positive correlations between sauna use and cardiovascular health and healthy blood pressure. Other benefits can include relaxation, stress relief, and increased heat tolerance.
However, these positive effects are greatest when combined with exercise; sauna use does not replace the need for regular exercise.
And the claims that sauna use “detoxifies” the body are overblown, ignoring the role of the kidneys and liver as the body’s primary toxin removers.
Finally, there are health risks with heat therapies…
Heat Therapy Hazards
First, heat accelerates inflammation. Applying heat to a brand-new injury with excessive swelling is asking for trouble.
Second, full-body heat therapies (think hot tub or sauna) create systemic fatigue, which can slow recovery and reduce performance.
Third, dehydration, dizziness and heat illness are major concerns, especially for individuals who aren’t acclimated to heat.
This precaution is particularly relevant to children and older adults, whose thermoregulation capabilities may be limited.
Adaptable Organism
Last but not least, remember that the human body is incredible adaptable. And adapting to heat is no exception!
After several bouts of heat exposure, the body adapts by sweating more efficiently, adjusting metabolic rate, and improving cardiovascular function for heat dissipation. Amazing!
Finally, stay safe outside during heat waves – use sunscreen, pace yourself, stay in the shade, go outside early or late, and stay hydrated (ideally with an electrolyte drink if you sweat a lot).
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