Performance Q&AThe big cycling questions answered by our team of expert coaches, nutritionists and riders
01 HOW DO I BOOST MY METABOLISM?
You’ve probably seen adverts galore proclaiming ways to accelerate your metabolism for a fitter, more attractive you. In cycling terms, this means a leaner, faster… and more attractive you! But is it really possible to raise your metabolism in search of peak pedalling performance?
First, the ‘boost metabolism’ headlines are talking about basal metabolic rate (BMR), which is your metabolic rate at rest. “Your BMR is the energy cost of fundamental physiological functions, including immunity, growth and thermoregulation,” says Javier Gonzalez, professor of nutrition and metabolism at the University of Bath. “It’s the minimal outlay to keep you functioning, and is why your brain and liver account for half your energy usage at rest.”
Which is why you can’t blame a slow metabolism for excess weight – this is only true if you have hypothyroid issues. In fact, the larger you are, the higher your resting metabolic rate: your body simply requires more calories to keep going.
Feed regularly
So, raising your BMR isn’t the way ahead unless you want to become a heavier, slower cyclist. At the other end of the spectrum, you want to avoid too low a BMR, which is worryingly common with endurance athletes who don’t eat enough in an effort to hit what they deem race weight.
It’s an issue a team led by Monica Torstveit of the University of Agder, Norway, looked into with their 2018 paper ‘Within-Day Energy Deficiency and Metabolic Perturbation in Male Endurance Athletes’ that featured in the International Journal of Sport Nutrition and Exercise Metabolism. In it, 31 competitive cyclists, triathletes and runners had their BMR measured, along with their energy balance – intake and expenditure – plus several blood parameters. Food intake was also monitored on an hourly basis.
The results? That 65% of the subjects had a suppressed BMR, down to larger single-hour energy deficits of more than 400 calories. To lose weight, they’d constantly refrain from eating. In body-fat percentage, it had the desired effect, as the 65% figures came in lower than the ‘normal RMR’ 35%. But it came at a cost as they expressed higher cortisol levels and a lower testosterone:cortisol ratio. Both impair recovery and can result in illness.
A further study
