The blood, sweat and tears of fitness

'Tis the season for fitness folly . . . with so many of us geting involved in marathons, triathlons and adventure races, JOANNE HUNTtakes a look at what happens to our bodies when we exercise and the smartest way to get fit

THE HELL of the West, the Beast of Ballyhoura, the Bull Raid – yes, the event calendar for Ireland’s growing number of extreme-challenge junkies is well underway.

Weekends of Olympic-distance triathlons, open water swims (no wet suits, please) and off-road biking in Ballygobackwards are the summer rewards now reaped by the thousands who have spent joyless winter nights pounding roads to get the miles into their legs.

But whether you’re a hardened triathlete or a novice fun runner, knowing a bit more about the body processes that lie beneath your lycra might just help get you over the line. And it all starts before you even leave the house.

“Even before you put on your gear, you might start sweating, feeling a bit clammy and anxious and your heart rate might rise in anticipation,” says Prof Colin Boreham of UCD’s Institute of Sport Health. “That’s just your autonomic nervous system, your ‘fright or flight’ mechanism getting you ready for action.”

So with simply lacing up our runners throwing our biology into gear, what happens when we hit the open road?

“When you start to run, you’re raising your energy requirements,” says Boreham, an Olympian decathlete and former fitness advisor to the IRFU.

With our muscles working to make us move, they demand more energy and oxygen to get the job done, Boreham explains. And because it is our blood that delivers this fuel to our muscle cells, our heart rate goes up to speed the delivery.

Our lungs kick in too, says Boreham. “Your breathing rate goes up to increase the amount of oxygen that can be absorbed into the bloodstream – so the heart and the lungs work together to increase oxygen and fuel delivery to the muscle cells.”

BUT IT DOESN'T STOP THERE.If you've ever started to run and felt wretched for the first kilometre before easing into your stride, it's probably because you haven't warmed up.

For Prof Phil Jakeman, a lecturer in the biochemistry of exercise metabolism at the University of Limerick, it’s all about muscles – and by hurtling them into action without prior notice, “you’re creating a deficit which can make you feel worse”, he says.

“You need to establish in the muscle a higher rate of metabolism in preparation for the exercise you are going to do,” explains Jakeman of the need for a warm-up.

“It’s better to start by brisk walking for a few minutes and then going into a jog than sprinting from the doorstep,” he advises.

A gentle start he says will increase blood flow and “without that blood flow, your muscles would get effectively starved of their oxygen and energy. You also generate heat and heat increases the viscosity of the muscle and makes it more fluid and easier to move.”

Comprising 80 per cent water, muscles are given structure by connective tissue. Jakeman says a warm-up also helps to loosen the adhesions between the muscle and connective tissue, making for freer movement.

Boreham says the muscle cell’s simple raison d’etre is to contract – but in doing so it produces a few waste products, including carbon dioxide and lactic acid.

“If you go off at a terrific sprint, your aerobic system [your breathing] doesn’t have time to catch up to release enough energy, so your anaerobic system kicks in – it’s a sort of emergency energy system.

“Your heart and your lungs take about a minute to get going and in the meantime, you have to get the energy from somewhere, so it comes from anaerobic sources [a chemical reaction occuring in cells without oxygen].”

Lactic acid is a waste product of anaerobic metabolism and its build-up can cause pain in the muscles and stop them from contracting properly.

Boreham explains that when 400-metre runners crumple after a race, it’s down to anaerobics. “I wouldn’t say you could do [400 metres] in one breath, but you don’t need much aerobic metabolism,” he says. “You need lots of anaerobic metabolism, and lactic acid is a by-product of that – that’s why they just go wobbly at the end of a race. The lactic acid causes their muscles to stop working.”

IF YOU'RE IN LOVE WITHsomeone who has started to exercise, you might begin to notice some other changes too.

“Your heart literally gets bigger,” says Boreham. “The chambers of the heart get larger and more muscular and you develop what’s known as ‘an athlete’s heart’,” he says. Bigger and able to push more blood around the body with fewer beats, typically the more trained the athlete, the bigger the heart and the fewer the beats. This might make them more relaxed and easygoing (but it can’t guarantee they’ll love you back).

Athletes are sweatier too. More efficient at expelling the heat produced by muscle activity, they tend to sweat sooner and more profusely.

Also, dinner dates with athletes are likely to be a carb-y affair. While Phil Jakeman says we carry enough fuel in the muscle to sustain about 90 minutes of fairly intense exercise, the dreaded “wall” happens when that fuel runs out.

He says while the average person would take about 3 to 4 grams of carbs per kilo of bodyweight, for athletes, it’s between 5 and 7 grams.

Water is important too, but for exercise lasting just an hour, he says, “this idea that you have to go out with your bottle of high carbohydrate this or that is a bit rubbish, to be honest”.

But what of the clamber of Ireland’s over-30s to extreme events?

With the average age of runners in the cult Connemarthon lying at 38, the King of Greystones triathlon 37, and with two-thirds of Dublin City Marathon runners aged between 30 and 50, what are they all running from?

“Power and speed start to diminish in your early 30s, but endurance keeps going,” says Boreham. So while we might be nostalgic for the vim that saw us sprint to gold at Mosney on nothing but a bag of Monster Munch, all is not lost as we age.

“Don’t forget, Eamonn Coughlan ran a sub-four-minute mile when he was 40-plus. There are lots of marathon runners in their 40s and 50s running 2 hrs 25 mins, which is still pretty elite,” says Boreham.

But what about the mind, can Ireland’s leading sports scientists tell us the secret psychological sauce to sporting success? “Yes,” says Boreham. “Overcome your inertia. It’s the single biggest problem for 90 per cent of the population.

“The thing to remember is that our bodies were designed for activity, they weren’t designed for sitting at a computer. When your body does start exercising, it starts to crave it because that’s the way we’re meant to be. We need to stop thinking of exercise as the abnormal state and start thinking of it as our natural state.”

The future of exercise

NEW TECHNOLOGY is revolutionising how we exercise, says Prof Gearóid O’Laighin, director of the Sports and Exercise Engineering degree at NUI Galway.

Students of the course, which mixes mechanical and electronic engineering with anatomy and physiology, are developing systems to encourage us to “use it or lose it”.

Describing the university’s work with smartphone sensors and apps (pictured), O’Laighin says when activity isn’t detected for a while, the phone gently prompts its owner to exercise: “The phone might say, ‘it’s really nice day, what about a walk?’ or ‘it’s not a great day, what about getting on the step machine?’”

Working with an exercise psychologist to develop the apps, he says: We want to imbed expert psychological knowledge so that they work effectively to get people to exercise – otherwise you could just end up annoying people.”

O’Laighin says the now-ubiquitous smartphone will play a huge part in the future of health and wellness. “Older people don’t want to be stigmatised by wearing special medical devices – a phone is something used across the generations. As we age, the apps can adapt to our changing needs.”

Meanwhile, Clarity, a research partnership between UCD, DCU and the Tyndall Institute in Cork, is using sensor web technologies to refine performance in sports such as tennis, hockey, cycling and even darts.

Developing on-body sensors for monitoring a variety of physical performance factors including location, movement, posture, and temperature, as well as respiration and heart rate, the information can be gathered and wirelessly transmitted to a coach for analysis.

Clarity researchers have also developed a sweat patch – no, not that kind – enabling the real-time collection and testing of the pH of human perspiration during exercise. The monitoring will ensure an athlete remains hydrated to peak performance.