Hydrotherapy: HOT vs. COLD

 By Ashley Walsworth RMT


One of the most common questions I get asked is “should I use hot or cold?” Surprisingly it’s not as simple of a question to answer as you may think, as both hot and cold affects the body in numerous ways, and there are many ways in which to use them. Let me tell you a little about how each works and then we can determine which one to use.

The common favorite choice is to use heat, aka Thermotherapy, so this is where I will start. Heat will bring circulation to the area, it is a vasodilator to start, meaning it will increase the size of your blood vessels and brings more blood flow to the areas you are treating. After several moments, about 15-20 minutes, your body starts to relax and the blood vessels will shrink back down to normal size. During the span of time when the blood vessels are vasodilated, the increased blood flow will get rid of any unnecessary toxins like lactic acid, unused glucose, or unwanted small amounts of fluid in the area. Heat can also help break the pain cycle (pain = spasm= more pain) which can help the muscle structures to relax, let go if any tension you are feeling and decrease the amount of pain felt. It feels nice to put a hot pack on your body, makes you feel warm and comfortable, but is not always the best choice to pick.

Cold, aka Cryotherapy, is commonly disliked by most of the population, although it is my personal favorite. In most cases, cold is used for longer than 1 minute, in which case it becomes a vasoconstrictor, meaning it shrinks the size of blood vessels, limiting how much circulation comes to the affected area. This slows down the bodies inflammation response, and lets the body get rid of excess swelling and bruising, which then allows the body to go through the proper healing stages faster. Also, cold decreases nerve firing, which creates an analgesic affect. Basically, that means that it will numb out the area so you don’t feel as much pain. Yes yes, I know that cold can be uncomfortable but the effects are amazing, which is why I like it so much!

Alright, now that you know a bit more about the effects of hot and cold, we can talk about when to use them. First you should ask yourself a couple questions. What does my pain feel like? Dull, achy, sharp and intense, deep and boring (usually found at a joint), or shooting electric? Do I have swelling or bruising where I feel the pain and does the site of pain feel hot to the touch? This will tell you whether you have muscle pain, joint pain, nerve pain or an acute injury where significant damage as been done to the tissue. If what your feeling is a dull ache pain and muscle tightness or fatigue, usually from hard workouts, or long hours of the same thing thought the day, and there is no heat or swelling in the area, then the use of Thermotherapy (hot) is the choice for you! Apply a hot pack/pad/bath to the affected area for approximately 15-20 minutes. Please please please make sure that the hot temperature is well within your comfort level. I don’t want people out there scalding themselves because I told them to put hot on their painful muscles! Always listen to your body first! If the heat starts to get uncomfortable or painful before the time limit is up, take it off! What if you’re the type of person that loves putting heat on themselves for hours on end? My advice to you is to follow the 15-20 minute time limit, take a break for 10-15 minutes and repeat the process. You can do this as many times as you wish. Applying heat for longer than 20 minutes at a time can cause the opposite affect and create more tension and pain than what you started with.


If what your feeling is sharp and intense, a deep boring feeling, electric type pain, or there is swelling, bruising or heat in the area, then Cryotherapy (cold) is what you need. Grab a cold pack or bag of ice and apply it to the affected area for about 10-15 minutes or until it goes numb, whichever comes first. Make sure you have a small barrier, like a thin t-shirt or towel, in between you and the cold. This will make sure you don’t accidentally give yourself frostbite. You will feel several sensations while using cold. First it will feel cold, then burning, then it aches, then numb. We call this series of feelings C-BAN, and it is important to allow yourself to go through all of them to get the full effects of the cold therapy. Repeat the cold therapy with 20-30 minutes in-between applications until the pain, swelling or bruising has diminished. Well, I hope you have learned a thing or two about the uses of hydrotherapy, and don’t forget, the highly-trained therapists a Three Peaks Clinic can help you with any pain you’ve got and answer any questions you have!

Happy Hydro-ing,

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