COLD-WATER SWIMMING
The promise
According to aficionados, it will boost your immune system, burn calories and leave you with an all-natural high.
Does it deliver?
There’s no doubt swimming boosts aerobic fitness, reduces fat and
increases muscle. Add icy water though, and the risks may start to outweigh the
benefits. “Immersion in cold water puts a significant strain on the heart,
increases your blood pressure, and leads to uncontrollable hyperventilation
that can be a precursor to drowning,” says Mike Tipton, professor of human and
applied physiology at the University of Portsmouth, and a keen triathlete.
This “cold water shock response” begins below
15C, and is responsible for most drownings in the UK (where the average water
temperature is 10C) – most often, the shock of the cold causes people to inhale
water, but it can also prompt heart attacks.
That’s not to say you can’t get used
to the cold. “Provided you go about it sensibly, as few as five, five-minute
immersions in cold water will reduce that shock response and the problems
associated with it,” says Tipton. Anyone considering outdoor swimming should
have health checks, be accompanied, and build up to longer swims at colder
temperatures slowly.
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Going into cold water will give you a
buzz and leave you feeling wide-awake, because it activates the fight or flight
response and releases hormones such as adrenaline and cortisol. But is it
better than regular swimming? The jury’s still out.
Several studies have found cold water
activates the immune system, but that isn’t necessarily the same thing as
improving the immune system. Neither is it clear whether you’d get the same
immune system boost by simply swimming in warmer water – this is something that
Tipton’s team is currently investigating.
Does it burn more calories? It
depends on how fast you’re moving. If you’re sitting still in cold water and
shivering, you’ll burn more than if you were on dry land, but who wants to put
themselves through that? Once you get moving and stop shivering, any difference
in the number of calories burned will be negligible, Tipton says.
SPINNING
The promise
No gym is complete without its
squadron of spinning bikes, often accompanied by pumping techno music and an
instructor hollering at the class. Spinning, or group indoor cycling, promises
to burn fat and boost strength and endurance as you power through virtual
sprints, hill climbs and headwinds - all without having to actually go
outdoors.
Does it deliver?
Generally, riding on a stationary
bike isn’t as good as the real thing. One recent study found cyclists produced
more power – and thus burnt more calories – for the same
perceived effort, when they were outdoors.
On the other hand, in a spinning
class you get the added benefit of a coach pushing you harder than you might
otherwise go cycling alone. “Outdoors can be quite strenuous, but it is more
self-paced,” says Carl Foster, director of the human sports laboratory at the
University of Wisconsin, La Crosse. “Face it, the instructors make their money
motivating people, so spinning classes tend to be at the upper end of the
intensity continuum.” In another study, Foster’s team found spinning class
participantsr regularly exceeded thei for
short periods – so were working very hard. Spinning should make you fitter and
burn lots of calories – just beware your appetite will also increase as a
result.
PILATES
The promise
Pilates combines elements of yoga and
martial arts training into a predominantly mat-based routine that it’s claimed
boosts strength, flexibility and posture. Celebrities, including Madonna and
Jennifer Aniston, swear by its body-sculpting powers, but pilates is also
recommended for those with back pain to strengthening muscles that support the
spine.
Pilates: loved by celebrities.
Photograph: Eliza Snow/Getty Images
Does it deliver?
A key claim is that it activates and
strengthens “core” abdominal muscles, which is probably true. In a recent
study, Duncan Critchley at Kings College, London and his colleagues
divided a group of regular gym users into two groups – one group did two 45-minute
sessions of pilates a week for eight weeks; the other did conventional weight
training – and then compared their abdominal muscles. “Those who had done
pilates training were using their deepest tummy muscles more than those who had
done the strength training,” says Critchley. In another study, he looked at the
effect of pilates on those with lower back pain, and found that while
most reported feeling better after a pilates course,
this didn’t necessarily correlate with how well their core abdominal muscles
were working.
Even so, pilates probably will make
you stronger. Another recent study showed that a twice-weekly class led
to significant increases in the endurance of musclesin
the abdomen and upper body, although it detected no improvements in posture or
balance.
HIIT
The promise
If you want to get fit, but never
have time, then HIIT (high intensity interval training) might seem the perfect
solution. The idea is to alternate very short (30 second) bursts of extremely
intense aerobic exercise with slower recovery periods. This is claimed to
produce the same benefits as more conventional aerobic exercise (such as
running or cycling) for far longer.
One idea is that HIIT is better at
depleting the glycogen – or sugar stores – in your muscles, than regular
exercise. “If you start breaking down this glycogen on a regular basis, the
theory is your muscles will get better at taking glucose up from the
bloodstream, and this could reduce your risk of diabetes,” says Niels Vollaard,
an exercise physiologist at the University of Bath.
Does it deliver?
Vollaard’s team found that
interspersing 10 minutes of easy peddling on a stationary bike with two
“all-out” 20-second sprints can achieve the same health
benefits as a 45-minute run or cycle ride. Even better, this seems
to suppress appetite, unlike more conventional exercise which makes you
hungrier.
The drawback? For now at least, most
gym bikes and treadmills are geared towards general aerobic exercise, rather
than sprint training. And although many gyms claim to offer HIIT classes, what
they often mean is interval training which, although hard work, is unlikely to
recreate the extremely high intensities of the HIIT research taking place in
sports science labs.
To do this, you need to find a static
bike that lets you switch the resistance from really low, to really high,
extremely quickly. Alternatively, look for a steep hill – ideally with a
downward slope immediately before it. The key is to get your legs moving as
quickly as possible before you hit the sudden increase in intensity – and then
you need to keep on peddling as hard as you can for another 20 seconds. Runners
could also try the same thing on foot.
Because of the strain HIIT puts on
your heart, Vollaard recommends consulting your doctor before starting any kind
of high intensity exercise.
CROSSFIT
The promise
“There is the pain that hurts you,
and then there’s the pain that changes you”. It’s a mantra beloved of
crossfitters who believe that to get results you need to push yourself hard;
very hard. Crossfit uses constantly varied, high-intensity, functional
movements – the sort we use in everyday life to sit down at a chair or lift a
bag off the floor – to get results. In crossfit, the loads you bear are far
heavier, and they’re performed in a competitive environment where you’re
encouraged to push yourself harder each week – often with little rest in
between.
Does it deliver?
Recent research suggests crossfit
delivers impressive results. When Steven Devor and his colleagues at Ohio State
University assigned 54 men and women to a five-day-a-week crossfit programme
for ten weeks, they saw big improvements in participants’
aerobic capacity (a marker of general fitness), a 3-4% fall in fat and
increases in muscle, regardless of initial level of fitness. “Crossfit
generally produces improved results when in body composition and measurements
of aerobic fitness compared to traditional weight lifting or aerobic exercise,”
says Devor – mainly because you are constantly working at a high intensity,
with few rests in between sets, he says. However, this may come at a cost. In Devor’s
study, nine of the participants dropped out because of injury.
MARATHONS AND BEYOND
The promise
Running is now second in popularity to swimming in the UK,
with booming numbers signing up for half-marathons and marathons. This is
prompting some to seek even bigger challenges, like ultramarathons or iron man triathlons. Those who compete in such
events tend to be extremely lean and fit, but is running – particularly for
long distances – really the best form of exercise?
Does it deliver?
It depends on what you want to
achieve. “If you just want to improve your health and to feel a bit better,
then regularly running five to 10km is great,” says Niels Vollaard, an exercise
physiologist at the University of Bath. “If you want to build slightly bigger
muscles and look a bit more trimmed then you probably want to do a bit of weight
training as well.” This is because although running will make your muscles
fitter, it won’t usually make them grow any bigger. Your goals will also
influence how hard you need to push yourself on each run. If you’re just
running for general health and wellbeing, then continuing to run the same
distance at the same intensity will continue to burn off excess calories and
reduce your risk of disease. But if you want to get even fitter, or improve
your time or distance, you will need push yourself harder – either running
longer distances, or incorporating some interval training.
This year’s London marathon.
However, regularly running longer
distances than 10K can have a negative impact on your health. “Training for a
marathon is a real challenge for your joints, tendons and cartilage, and so we
tend to see regular distance runners developing problems with their knees, hips
and shins,” says Vollaard. “Your muscles are happy to keep on adapting and
getting better, but the rest of your body will struggle.” And although runners
generally have healthier hearts than people who don’t exercise, emerging
evidence suggests that constantly training for, and competing in, extreme
endurance events such as marathons, ultramarathons, ironman triathlons, and
very long-distance bicycle races, might damage the heart and blood vessels.
Before considering any exercise
regime, always consult your GP. Never undertake any form of exercise that may
be strenuous, unusual or intense without taking medical advice.
Source: http://www.theguardian.com/lifeandstyle/2014/dec/05/exercise-hiit-spinning-running-swimming-pilates-review
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