It’s not a coincidence that the number of weight loss articles, gym memberships, and new diet books all spike in January. People set New Year’s resolutions to get in shape and perhaps lose some weight they gained during the Holidays. Cyclists have a complicated relationship with bodyweight because there can be a performance advantage to being lighter when trying to pedal uphill, but an overemphasis on weight and aesthetics can have a negative effect on body image, self-esteem, performance, and both physical and mental health. To help keep the idea of weight loss in perspective, it’s important to dispel a few myths.
There is no perfect shape, size, body type, or bodyweight for a cyclist. Or, put another way, cycling is a perfect sport for people of all shapes, sizes, body types, and bodyweights. Across the many disciplines of cycling competitions, certain characteristics become more or less advantageous. For instance, track sprinters, downhill mountain bikers, and BMX racers may benefit from a more muscular – and hence heavier – build compared to road and cross-country mountain bike racers.
Yet, even in the cycling disciplines that feature climbs and favor leanness, lighter is not always better. Losing too much weight – and the amount of attention required to lose it – can lead to undernourishment, compromised immune system function, diminished recovery from training, diminished or stalled adaptation from training, disturbed sleep, and more. Over a longer period of time, consuming too little total energy in an effort to maintain a low bodyweight can lead to Relative Energy Deficiency in Sport (RED-S), which can impair metabolic rate, bone health, immunity, protein synthesis and cardiovascular health in men and women, and menstrual function in women (Mountjoy et al. 2018)
You are better off focusing on the power side of the power-to-weight ratio. Train to improve your fitness and power output and eat to support your training.
You can’t outride your diet. The math simply isn’t on your side. At a moderate endurance pace, a cyclist might expend around 600 Calories in an hour. During a hard interval session or race, that energy expenditure may increase to around 1000 Calories per hour. You can consume 600 to 1000 Calories in a matter of minutes.
The other reason you can’t just ride more to lose weight is that more hours or miles on the bike creates greater fatigue, meaning you need more recovery time between rides. There is a limit to the amount of training time you can add before you no longer have adequate time to balance it out with recovery. Similarly, you can’t just increase the intensity because the amount of training stress you can cope with is limited by your current fitness level.
There’s an adage that fitness happens on the bike and weight loss happens in the kitchen. It’s not quite that black-and-white, but athletes looking to lose a few pounds can get there by a combination of slightly increased energy expenditure (add 15-30 minutes on to your rides) and moderate caloric restriction. In reality, it’s better to think of “moderate caloric restriction” as “eat enough to optimally support your training and lifestyle and reduce consumption of excess calories”.
There is some truth to this one; fat oxidation does increase when cyclists ride at moderate intensities in a fasted state or with low carbohydrate availability. However, the benefits are minor, you can achieve the same result with fundamental training methods, and there are some potential downsides to fasted training.
For one thing, training to improve aerobic endurance already increases fat oxidation and most amateur cyclists have plenty of room to improve fat oxidation through fundamental training. You’re better off training to improve aerobic endurance and sustainable power output because that fitness enables you to perform more work per minute, which increases energy expenditure per minute and the percentage of that energy coming from fat. More importantly, you are training to improve fitness and performance, not merely to burn fat calories.
There is also a potential downside to manipulating energy availability to optimize fat oxidation. It can lead your body to downregulate your capacity to use carbohydrate for energy during hard efforts (Burke et al. 2021). If you’re a competitive cyclist or want to keep up at the fast group ride, there is no prize for the rider who burns the most fat. To go fast you need to be able to produce power from fat and carbohydrate as quickly and efficiently as possible; a nutrition or training strategy that downregulates your capacity to produce energy from carbohydrate during high-intensity efforts is not advantageous.
The final reason to be careful with fasted training is that it can have unintended consequences for other areas of your training program. The key to fasted or low-carbohydrate availability training sessions is keeping the intensity low. If those sessions are too intense you are just increasing the energy and time required for recovery and putting the quality of future training sessions at risk. In the bigger picture, high-quality training sessions – supported by adequate energy consumption and recovery time – will do more to develop your power and fitness than the minor improvements you might achieve in fat oxidation through fasted training.
So, although the New Year inevitably brings with it all manner of products and pitches for weight loss, remember that cycling is a sport for people of all sizes and you are and can be a cyclist exactly the way you are.
References:
Burke LM, Whitfield J, Heikura IA, Ross MLR, Tee N, Forbes SF, Hall R, McKay AKA, Wallett AM, Sharma AP. Adaptation to a low carbohydrate high fat diet is rapid but impairs endurance exercise metabolism and performance despite enhanced glycogen availability. J Physiol. 2021 Feb;599(3):771-790. doi: 10.1113/JP280221. Epub 2020 Aug 19. PMID: 32697366; PMCID: PMC7891450.
Mountjoy M, Sundgot-Borgen JK, Burke LM, Ackerman KE, Blauwet C, Constantini N, Lebrun C, Lundy B, Melin AK, Meyer NL, Sherman RT, Tenforde AS, Klungland Torstveit M, Budgett R. IOC consensus statement on relative energy deficiency in sport (RED-S): 2018 update. Br J Sports Med. 2018 Jun;52(11):687-697. doi: 10.1136/bjsports-2018-099193. PMID: 29773536.
