What is your metabolic age?
As part of the series Move It, Lee Kenny looks at how our lifestyle, including exercise, may impact on our longevity.
I’m the first to admit I’ve let things slide. I’ve always been physically active but with a deskbound job and a love of an IPA I’ve noticed my jeans were a little tighter of late and there was a bit more middle than there used to be.
Knowing there was work to be done to stop my early middle-age spread, I agreed to undergo body composition and metabolic age testing.
I was one of five volunteers, aged from 23 to 87, to be examined at The Zone, Ara Institute of Canterbury’s Sports Science and Wellness Centre, in Christchurch.
Included in the group were a former marathon runner, a social smoker and a cancer survivor.
I hoped my metabolic age would at least be close to my actual age of 41 but when I was told it was comparable to the average 50-year-old I was surprised and dismayed – realising I’d taken my health and my waistline for granted.
We met Stacey van Maanen, manager at The Zone, and Kim Johnston, manager of the Sports and Recreation Centre.
They explained the process before measuring our height and programming our details into a body composition analysis machine.
The 30-second test involved standing on a scale while a small electrical charge was passed through our bodies to measure water, fat and muscle mass.
Stacey van Maanen said, unlike conventional scales, the system shows the distribution of body fat and muscle mass.
‘‘Where there is resistance, that means there’s some fat there.’’ The electrical current flows freely through muscle and water, she said.
A few minutes later and we were handed a print-off with data that included our skeletal muscle mass, per cent of body fat (PBF), body mass index (BMI) and basal metabolic rate (BMR).
My muscle mass was within the normal range and BMI was passable but four weeks’ worth of Christmas excess had pushed my waist-hip ratio above average.
Next we stepped on to the Tanita scales to gauge our metabolic age, before nervously awaiting the results.
Jonathan Guildford, 23, was
given a metabolic age of 20 despite his current level of physical activity being ‘‘relatively low’’.
‘‘Through most of my schooling years, I was very physically active and would be playing some sort of sport every day of the week,’’ he said.
‘‘Nowadays, I’m lucky to be doing some sort of physical activity about three times a week, so I was surprised to have the metabolic age of a 20-year-old.
‘‘Even though my results were much better than I expected, the test has made me realise how important it is to live a healthy lifestyle and has motivated me to exercise more and to return later in the year for another test.’’
Emma Dangerfield, 44, who describes herself as a prolific drinker and a social smoker, was given a metabolic age of 29.
The mum-of-two said her current level of activity only ‘‘extends as far as walking the dog every day’’.
‘‘I have participated in the odd triathlon, 10-plus years ago, and am prone to sudden bouts of panic resolutions to get fit. Fortunately these usually subside after a visit to the gym or a run around the block,’’ she said.
‘‘To score a metabolic age 15 years my junior was certainly one of the high points of the year. However, I’m sure I somehow cheated the system as I was the least fit of all the guinea pigs.
‘‘I think I am basically lucky to have been born to parents with healthy genes. I enjoy a healthy and varied diet, and I have a good base level of fitness, if only from chasing a dog and two kids around the house on a daily basis.’’
Martin van Beynen, 61, was given a metabolic age of 65. He said he wasn’t surprised by the results but was ‘‘hoping for better’’.
The dad-of-three – who underwent six months of chemotherapy for cancer in 2012 – has never smoked and although he used to do a lot of exercise, said he doesn’t currently do a lot.
‘‘I realise I’m a big boy but didn’t appreciate what this was doing to my biological age,’’ he said.
‘‘I’m still a little dubious but it’s still galling to have led a fairly active life for many years to go to seed like this.’’
Retired hotelier Eric Hunter, 87, was the oldest of the group but after a lifetime of running and cycling he scored a metabolic age of just 72.
The octogenarian has previously run 10 marathons but he was surprised by the outcome as he has not been as active lately, following a recent ankle operation.
‘‘I’m more than happy with the results of the test,’’ he said.
‘‘I haven’t done anything extraordinary, I’ve just carried on with my normal life, with the exception of having my moon boot on.
‘‘It’s most important to lead an active life, it doesn’t take long, just a little exercise every day is the answer to a healthy life.’’
And Stacey van Maanen said even small changes can make a difference.
‘‘Our biggest message is that we want everyone to try to improve their health to prevent non-communicable diseases such as heart disease, diabetes and cancers.
‘‘The main ways in which we can do this is moving more, eating well and practising mindfulness to reduce stress.’’
About the Basal Metabolic Rate test
The BMR test is based on a person’s basal metabolic rate, or the minimum amount of energy a person needs to sustain vital body functions while resting. It can be thought of as how much food someone would need to stay alive while lying on a couch.
The test compares an individual’s basal metabolic rate with the average rate for people that age. If theirs is higher, it indicates the person needs to improve their metabolic rate by exercising more and eating better.
Basal metabolism rises as a child matures and peaks at about 16 or 17, after which it typically starts to decrease. A slow BMR will make it harder to lose body fat and overall weight.
Van Maanen said the BMR test is only one value and does not give a good overall picture of a person’s health.
However, when it is considered with the other tests such as BMI and body fat, it provides a more reliable snapshot of a person’s health.
While it was important to know these figures for a person’s health, sometimes taking the tests could be detrimental to a person’s mental health and some may find it demotivating, she said.
‘‘It really depends on the person whether they should do a body scan or not.
‘‘If you’ve always struggled with weight your whole life, there’s no point in jumping on a scale because you know what it’s going to say anyway, so it’s more about increasing exercise in any way you can, eating nutritious food and trying to reduce stress in your life.’’