If every run, row and rep is feeling a little tougher than it used to, it can be tempting to pin the blame on the passage of time. Hollywood’s veteran action heroes, after all, are surely the exception, not the rule. But how much of an impact does age have on our PBs?
‘From their mid-twenties people typically lose about 10% of their VO² max [a marker of aerobic fitness] per decade,’ says exercise physiologist Tom Cowan. ‘After 50, this decline usually accelerates.’ Age-related muscle mass, or sarcopenia, also kicks in from around age 30, occurring at a rate of about 3% to 5% per decade.
That might sound a bit gloomy. But think about it: that’s just 1% of your fitness lost each year. To frame it another way, the average person in their forties can run 5K just two minutes slower than someone in their twenties. Are the changes you’re noticing more dramatic than that? Then there are likely to be other culprits.
It’s difficult to untangle cause and effect. One study of middle-aged men by the University of Sydney, Australia, concluded that declining testosterone was more likely to be a consequence of deteriorating health – expanding waistlines, reduced activity – than a cause. Our creaking joints and lingering fatigue can as much be a symptom of too much time behind a desk as they are a hindrance when we finally make it to the gym.
So, ask yourself: what else has changed? Are you sleeping less? Eating less protein? Are you still making it to the gym three nights a week, but finding yourself too distracted by work and family commitments to fully engage?
If lack of time is a problem, swap trundling on the treadmill for short blasts of high-intensity work on the bike, rower or SkiErg. When weight training, switch your focus to compound exercises, such as squats, bench presses, pull-ups and deadlifts, aiming to include two moves per major muscle group each week. And don’t skip your mobility work, either – ageing is associated with a loss of flexibility, too. You’ll be back on form by your next birthday.