Hot vs cold: what do your sore muscles need?

You may have seen athletes on social media wincing in ice baths or standing in metallic chambers… they’re doing cryotherapy, a recovery practice with plenty of fans, especially in the fitness world.

But if cryotherapy is so hot, does that mean the heat pack you’ve been using on your tight and screaming muscles is a waste of time?

WHAT IS CRYOTHERAPY?

 “Cryo” is derived from an ancient Greek word meaning “ice, cold, chill or frost”. Cryotherapy actually refers to any treatment that uses cold temperatures, which includes everything from putting a bag of frozen peas on a sore leg to freezing off warts.

In the fitness world, it generally refers to full-body immersion in the cold, either through cold water (an ice bath) or via whole-body cryotherapy (a chamber at a specialized clinic that is filled with cold air.)

Advocates say cold therapy can reduce pain and inflammation, aid rehabilitation, and reduce the likelihood of injuries – the theory being that if exercise leads to muscle inflammation and cold reduces inflammation, then making your whole body super cold must be great for recovery. 

This is why some people swear by cryotherapy being an essential part of any fitness routine, particularly for athletes and high performers. But what about the rest of us non-pros?

DOES IT WORK?
The thing about cryotherapy is that research is all over the place. Most studies have been small and have explored different temperatures and exposure times, making for inconsistent outcomes.

But on the surface, the science makes sense: intense training damages your muscle tissue (by design – that’s how you get stronger) and can result in inflammation, which leads to pain, tenderness, tightness, and loss of muscle strength. Jumping into the cold reduces blood flow, which then reduces inflammation and swelling. Plus, the numbing effect can temporarily reduce pain. 

If we want to look closer at the research to make a call on whether it works or not, we need to look at cold-water immersion and whole-body cryotherapy (WBC) separately. 

COLD-WATER IMMERSION
The Insta-friendly method is usually practiced for between 5–10 minutes in a bath filled with ice and water. The scientific consensus is that while the logic on cold-water immersion adds up, detailed research is lacking. Cold-water immersion has been found to ease delayed-onset muscle soreness (DOMS) – but only in comparison to doing nothing after exercise.

WHOLE-BODY CRYOTHERAPY
This futuristic method – usually done in specialized clinics – involves entering a chamber (up to your shoulders or neck) to get blasted with cold air, usually between -110°C and -140°C (-166°F and -220°F). A review of research into WBC in 2017 concluded that muscle pain was reduced 80% of the time the therapy was used, but the wide variations in how it was practiced (i.e. duration and temperatures) meant it was too early to recommend it as a reliable recovery technique.

SHOULD YOU TAKE THE PLUNGE?
The good news is, cryotherapy seems to improve subjective measures – people often report feeling more energized after taking a dip. But more research is needed to make any solid judgments on the cold hard benefits. 

Elite athletes and those who train at a similar level might find it is beneficial or feel it gives them an edge. So before you invest in treatment or fill your entire freezer with ice cube trays, make sure you have the basics down: adequate rest, sleep and nutrition remain the easiest ways to recover and perform at your best. If you’re already struggling to keep up with these tried and tested methods, cryotherapy probably isn’t worth it for you. 

That said, people have been swimming and bathing in the cold to improve their health for centuries. So if you enjoy it and find it revitalizing, keep it up! But don’t expect cryotherapy to change your life or turn you into a recovery superhero. 

Before you dive in, we’ve got one very important safety message: Cold therapy can be dangerous if done for too long or at the wrong temperatures. You should consult your doctor or health professional before trying cold therapy.

HOT VS COLD: WHICH ONE DO I NEED?
Now that we’ve looked into the science behind cryotherapy, let’s get practical. You’ve hurt yourself during your epic training efforts and you want to know whether to use an ice pack or a heat pack.

Generally speaking:

· Cold reduces inflammation and can numb pain, therefore it should be used on a recent injury (occurring within the last few hours) that involves swelling.

·  Heat increases blood flow and relaxes tissue, so should be used on sore muscles not caused by a recent injury.

So here’s when to reach for one or the other:

Use cold if:

·         You’ve just strained, sprained or pulled a muscle or joint.

·         You are experiencing swelling at the injury site.

Use heat if:

·         Your muscles are tight or tense.

·         You have a muscle cramp.

·         You have regular, dull aches and pains caused by prolonged sitting or bad posture (e.g. lower back, neck).

Never use extreme heat, and never place ice directly on your skin. If pain persists or restricts your training, consult a professional.