Hot and cold therapies: When to use what

We're all familiar with the scenes: footage of elite athletes being wrapped in aluminium foil or submerging themselves in an ice bath post-event; gym goers piling into the sauna or steam room post-workout; parents whipping out the wet flannel after their little one takes a bump to the head.

But does treating pain with heat packs or cold compresses actually work? And how do you know whether you should be getting the ice trays or the heat packs prepped?

Cryotherapy - the cold hard facts

"Cold therapy - or 'cryotherapy', to use its technical term - covers everything from those infamous ice baths to ice packs, coolant sprays and even the emergency bag of frozen peas you turn to when there's nothing else to hand," says registered physiotherapist Andy Britten.

In fact, the health benefits of cold therapy are heralded as being so holistic that whole body cryotherapy - a process that involves stripping bare and standing in a room chilled with liquid nitrogen to temperatures as low as -160°C for two to three minutes - has become one of the hottest health trends of the past few years.

While the jury is still out on whether this is a clinically proven injury management technique, what we do know is that localised use of cryotherapy to an injured area can be incredibly effective.

So, how does it work?

"Localised cryotherapy is basically the external application of intense cold to an affected area. It helps to reduce blood flow, which, in turn, helps to reduce inflammation while simultaneously reducing nerve activity to alleviate pain," says Andy.

What should I use it for?

Cold therapies are most effective in treating acute injuries or pain - particularly when they're used as part of the time-old RICE (rest, ice, compression, elevation) tactic.

"Use targeted applications to treat things like rolled ankles, bruises or contusions, and immersion therapies, like a cold bath or shower, immediately after a strenuous workout to relieve muscle soreness," advises Andy.

As part of immediate first aid for sprains and strains, Andy recommends applying a cold pack to the affected area for 15 minutes every two hours for 24 hours, then for 15 minutes every four hours for 24 hours.

"Bear in mind though that while cold therapy is effective in relieving post-workout aches and pains, it doesn't actually repair damaged muscles - you'll need to go heavy on the 'rest' part to give those sufficient time to heal."

Burning questions about heat therapy?

The first thing to be aware of is that there are two elements to heat therapy: dry heat treatments - which include the likes of saunas, electric heat pads and heat rubs - and moist heat treatments, like steam rooms, hot baths, steamed towels and hot water bottles.

While dry heat can usually be applied continuously for up to eight hours, moist heat is recommended to be used in two-hour cycles.

How does it work?

"Heat therapy basically acts in the exact opposite way to cold therapy," says Andy. "It increases blood flow to the affected area, rather than restricts it, which directs more oxygen to the joints and muscles surrounding the source of the pain for greater relief."

What should I use it for?

Generally speaking, heat therapy should be used for chronic pain. Think back and neck pain or spasms, along with osteoarthritic symptoms like joint discomfort and stiffness.

"Just don't use it in instances where the skin is broken, or your body temperature is already elevated," advises Andy.

Heat therapy can also play its part in the pre-workout warm-up by encouraging tissue elasticity which gives muscles more flex and stretch. And if your ice bath hasn't managed to put a stop to delayed onset muscles soreness (DOMS) altogether, it can also be used to alleviate all-over body aches after a workout, too.

One more thing

If you're using cold therapy to treat an injury, switch to heat-based methods after two or three days. The remedial benefits of cold therapy are believed to become less effective as time goes on.