Hot or cold shower after training? We've revealed the best choice!

By Dr. Will Murtagh

Rest days are crucial to our performance, and you can do more to speed up the recovery process and get yourself in the best shape to train hard, recover, and then come back to be ready for the next workout. One way to promote recovery is to immerse yourself in water, which will kick-start the recovery process. However, there are differing opinions on what temperature is appropriate for improving recovery. Some sources claim that immersion in cold water is best, while others prefer immersion in hot water.

In this guide, we'll delve into that as well, but more into concepts related to recovery and then explore the pros and cons of both cold and hot water showers. This will help you decide what's best for you. This will help you recover faster from your workout and keep your training as intense as possible.

Ways to recover when using water

If you want to improve your recovery or recovery, there is probably a product or service that claims to do it for you. There are several different types of recovery modalities on the market today. These can range from pneumatic boots and saunas to manual techniques such as massage and devices such as transcutaneous electrical nerve stimulation (TENS) units.

One of the most researched methods for improving recovery is immersion in ice bath water or simply showering after a workout. Research on which temperature is best is conflicting, with both methods showing positive benefits depending on which study you read. In my eyes, however, there is one clear winner. First, though, let's recap the benefits of both hot and cold showers.

The case for cold showers

The most common method of water therapy for improving recovery is cold water. At the most basic level, training produces a great deal of heat in the body, which can also be a source of fatigue if not properly managed through the sweating process. It is logical, then, that trainers and athletes alike will want to immediately step into a cold shower to cool down after a hard workout. However, a cold shower after a workout is not just refreshing^.1

Reducing inflammation

The use of cold temperatures on inflamed joints, whether after injuries or surgery, has been done for many years. The concept of using cold temperatures to reduce inflammation in the body is based on vasoconstriction, or the narrowing of blood vessels, which prevents increased flooding of swollen joints with inflammatory substances. This concept also applies to cold showers after exercise, as joint inflammation can occur as a result of everyday events during heavy training when the impact on the joints is high. Cold showers can have a global vasoconstrictor effect and help reduce inflammation in sore joints. Cold showers can also have an effect on relieving joint and muscle pain. This numbing effect reduces the perception of pain and indirectly reduces the inflammatory response.

Reduction of delayed onset muscle pain (DOMS)

Delayed onset muscle soreness or "DOMS" is a training phenomenon that can negatively affect your ability to train consistently. DOMS is characterized as pain and stiffness that occurs in the days following exercise and peaks approximately 48 hours after training. It can occur if you are just starting or returning to training. As well as if you have been training for a while and have recently changed your exercise selection or shifted your training in some way, such as increasing the weight you use or the number of reps for a given workout^.2

Some soreness is expected after a workout, but if it is severe, it can be problematic. Cold water therapy has been shown to reduce DOMS in the days following a workout. This is in response to the effect that freezing temperature has on tissue temperature and the speed of nerve conduction of pain fibers^.2

Improving blood circulation

Improving blood circulation throughout the body may seem counterintuitive based on what I have stated above regarding blood flow limitations with cold water treatment. The cold temperature causes constriction of blood vessels and restricts blood flow throughout the body. However, it improves blood circulation due to the rebound effect once the mean temperature is removed. When the blood vessels in the body relax and return to their standard diameter, there is a rebound of increased blood flow to account for this and compensate, thus improving the rate of blood circulation throughout the body^.3

This is important for recovery because abundant blood flow to the body's muscles, organs and joints brings nutrition and other recovery substrates to the area to replenish what was consumed during training. These include carbohydrates, amino acids and electrolytes such as sodium and potassium.

The case of the hot shower

Although it may seem counter-intuitive to take a hot shower after you've worked up a good sweat during your workout and raised your body temperature, a hot shower after a workout has some benefits. Also, some people may not tolerate cold temperatures well, so for them, a hot shower will be a better option to improve recovery.

Acclimatising to the heat

This is probably the most significant benefit of a hot shower after training if you work, train or compete in climates where the temperature is high, such as soldiers, athletes or rescue workers. The inability to regulate your body temperature can be a source of fatigue during training and competition. In fact, exercising in hot climates creates additional stress on your body that can negatively affect brain function, ventilation rate, and muscle metabolism if you are not well adapted to it^.1;4

Taking hot showers after training can help your body adapt to these hot climates and improve your performance during training or competition. Doing so can help you train at a higher intensity, and the longer and more often you can sustain high-intensity training, the higher your performance will climb^.4

For competitors, especially in sports where your ability to stave off fatigue determines the winner, such as track and field, CrossFit, and cycling, the person who can keep their body relaxed longer usually has the best chance of winning.

Increased blood flow

Hot water showers can help with recovery after a workout because the warm temperature allows the muscles of the blood vessel walls to relax, increasing their diameter (vasodilation), and thus increasing blood flow to the muscles. This allows more blood to pass through the blood vessels, which reaches the muscles more quickly and effectively provides them with the nutrition they need for rapid recovery and repair^.5

Increased blood flow also facilitates the removal of waste products produced during exercise, such as lactic acid, ammonia and carbon dioxide (CO2), from muscle tissues. Each of these substances is removed by the blood and then either converted into a new substance to be used as fuel (lactic acid) or excreted in the urine (ammonia) or into the lungs (CO2).

Is a hot or cold shower better after a workout?

As you can see, there are arguments for both hot and cold showers. However, according to the available research, cold showers will most significantly affect your ability to recover and prepare for your next workout. Although several studies have reported the benefits of hot water after exercise, many have shown no positive effect on recovery. Thus, the effect of hot water on post-exercise recovery is unclear^.7

So if you're looking for a way to boost your recovery, and we're not talking hypertrophy here, I would opt for a cold shower after your workout.

However, if you have difficulty tolerating cold temperatures, such as those who suffer from Reynaud's disease, where blood vessels in the body excessively constrict in response to cold, then a hot shower may still provide some benefit. Now you have another method in store to optimize recovery and continue your hard training. So take advantage of what you now know, start incorporating water therapy into your post-workout routine, and watch your results skyrocket.

Studies used

1. Nybo, L., Rasmussen, P., & Sawka, M. N. (2014). Performance in the heat-physiological factors of importance for hyperthermia-induced fatigue. Comprehensive Physiology, 4(2), 657-689.
2. Wang, Y., Li, S., Zhang, Y., Chen, Y., Yan, F., Han, L., & Ma, Y. (2021). Heat and cold therapy reduce pain in patients with delayed onset muscle soreness: A systematic review and meta-analysis of 32 randomized controlled trials. Physical therapy in sport : official journal of the Association of Chartered Physiotherapists in Sports Medicine, 48, 177-187.
3. Yeung, S. S., Ting, K. H., Hon, M., Fung, N. Y., Choi, M. M., Cheng, J. C., & Yeung, E. W. (2016). effects of Cold Water Immersion on Muscle Oxygenation During Repeated Bouts of Fatiguing Exercise: A Randomized Controlled Study. medicine, 95(1), e2455.
4. Zurawlew, M. J., Mee, J. A., & Walsh, N. P. (2019). Post-exercise hot water immersion elicits heat acclimation adaptations that are retained for at least two weeks. Frontiers in physiology, 10, 1080.
5. Wilcock, I. M., Cronin, J. B., & Hing, W. A. (2006). physiological response to water immersion: a method for sport recovery. sports medicine, 36, 747-765.
6. Jackman, J. S., Bell, P. G., Van Someren, K., Gondek, M. B., Hills, F. A., Wilson, L. J., & Cockburn, E. (2023). Effect of hot water immersion on acute physiological responses following resistance exercise. Frontiers in Physiology, 14.
7. Versey, N. G., Halson, S. L., & Dawson, B. T. (2013). water immersion recovery for athletes: effect on exercise performance and practical recommendations. sports medicine, 43, 1101-1130.