Health benefits in cold water immersion

COMMITTED: A lone swimmer enjoys the benefits of taking a plunge in the Merewether Ocean Baths on a fine winter's day last week. Picture: Marina Neil
COMMITTED: A lone swimmer enjoys the benefits of taking a plunge in the Merewether Ocean Baths on a fine winter's day last week. Picture: Marina Neil

Have you ever wondered why on earth people are swimming in the baths through winter?

I have, especially when I have seen them religiously taking the plunge before the sun is up in the depths and darkness of winter.

I am more of a “fair-weather” ocean baths participant but, when suffering some ongoing body stiffness of late, that’s exactly where I ended up.

Granted, it was the middle of one of these mild winter’s days we’ve been having, which made it easier to get it, but after the burning cold sensation eased and I got my breath back I could certainly see the attraction.

I had just completed two games of football but almost instantly I felt relief. I also felt invigorated, not to mention a little bit tough for taking on the 15/16 degrees stated on the daily temperature board at the Merewether Ocean Baths.

I found myself researching the topic after my own experience. An article on Estonia’s official tourism site calls it “the Estonian vitamin” and, according to visitFinland.com, it will leave you feeling “fantastic and refreshed”.

They were talking about ice or winter swimming and there are plenty of clubs devoted to it, including a few of our own such as the Merewether Mackerels, who swim at the baths Sunday mornings from May until September.

It is also common to see sporting teams hitting the ocean, pools or ice baths after a game or hard training session.

A couple of the articles I read also suggested that cold water swimming could boost your immune system and help stave off illness.

I wasn’t up to doing laps just yet. I thought I might work up to that. Instead I jogged around a bit before psyching myself up to duck under. I was there mainly to hopefully prevent the feeling of waking up a day or so later and feeling like the Tinman.

When I wanted to find out the science behind it, physiotherapist Dave Naylor, from Ethos Health, told me the principle of cold water recovery revolves around “recovery from training or exercise, where you are trying to restore and regenerate the body to its normal levels”.

The Merewether Mackerels reap the benefits of swimming through the colder months, taking the plunge every Sunday morning at the Merewether Ocean Baths from May until September. Picture: Jonathan Carroll

The Merewether Mackerels reap the benefits of swimming through the colder months, taking the plunge every Sunday morning at the Merewether Ocean Baths from May until September. Picture: Jonathan Carroll

“To improve our fitness levels you have to work hard, and in general terms hard means ‘fatigue’, and cellular disturbance,” Dave said.

“The end result of that in the hours, and in some instances days, following exercise, is that you can get sore. Therefore you need to ‘recover’ from fatigue caused by hard training or sport to get the best follow-up performance.

“The efficacy of cold water immersion or cold water therapy has not been clearly established, but the principle is thought to work around reducing core body temperature and subsequent pressure-induced changes which reduce blood flow (vaso constriction) and muscle (tissue) temperature.

“The net result of this, it is proposed, results in reduced tissue inflammation post strenuous exercise. The reduction in inflammation might then be attributed to reducing delayed onset muscle soreness [DOMS] and enhanced recovery of muscle function.”

But how long and how cold should the water be? 

“Not surprisingly there’s a few considerations,” Dave said. “For high aerobic strenuous sports where you want to cool excessive body temperature you can be looking at around 10 minutes in 15 degree water. You’ll commonly see AFL or soccer players wading in the water off Port Melbourne for this, as their legs have had a high aerobic workout.

“For other contact sports where you want to reduce inflammation of tissue from collisions, temperatures of 11 to 12 degrees for short bursts of 30 to 60 seconds three times is indicated. Because everyone of us is built a little bit differently with a bit more or less tissue (fat), there will be a bit of variation, but these are some numbers to work around.”

And, according to an article in the Herald on Saturday, it’s a good time to be in the ocean too with locals reporting some of the clearest waters around Newcastle for a while.

Upcoming Fitness Events

Lake Macquarie Running Festival, Warners Bay, August 26: Held on the shores of Lake Macquarie, there is a 21.1km half marathon course, a 10.5km fun run and 4km kids’ scamper.

Variety Spin 4 Kids, Harbour Square, September 7: A six-hour cycling charity event to help disadvantaged children of the Hunter. It is on stationary bikes and teams comprise up to 10 riders or you can do it solo.

The Bloody Long Walk, Newcastle, October 7: A 35km trek from Belmont to Newcastle Beach, taking in Fernleigh Track and Memorial Walk. It is raising funds and awareness for Mitochondrial disease.

Winter Warmer Workouts Week #9

This week it is the beach workout, so you can take a plunge after or at least put your legs in to help reduce any soreness in the days to follow.

In winter, the sand can get pretty cold under foot, so choose a time or day when the sun is out and the wind is limited to stop your feet feeling like they are going to freeze off.

Set two markers, roughly 20 metres apart. Pick out at least five exercises – squats, push-ups, lunges, bent-over rows and core. Do one-minute sets for each separated by one-minute runs, walks or bear crawls between the markers. 

Three times through will be a 30-minute workout.

Renee Valentine is writer, qualified personal trainer and mother of three. r.valentine@fairfaxmedia.com.au.