Have you ever been in a spin class - or walked by the spin bikes at the gym - and wondered if triathletes should use spin bikes, or ifspin bikes give you as good (or better) a workout as riding your tri bike outdoors? You’re about to find out in this comparison of the advantages and disadvantages of spin bikes vs. regular bikes.
Spin Bikes Are Different
The majority of spin bikes are different than normal road, mountain or triathlon bikes because they have a “fly wheel”, which is a 30-40 pound wheel that provides the resistance as you pedal (and which is also the reason that the pedals on a spin bike keep moving after you stop pedaling).
Because of this fly wheel, your hamstrings work harder to slow the pedals as they come around. But when you’re outdoors, you’re pedaling against the friction of road resistance and wind resistance, and this motion requires more work from your hip flexors and quadriceps.
That fly wheel keeps the pedals spinning after you get the pedals moving, so it’s also very easy to let a spin bike do the majority of the work for you, which is why many people in a spin class appear to be pedaling very fast when they’re actually not doing much work at all (to see more dangerous examples of people doing stupid stuff in a spin class, check out THIS article.
So, now that you understand the difference between spin bikes and regular bikes, let’s look at whether triathletes should actually use spin bikes.
Spinning vs. Cycling – Overall Fitness
Spinning: A study by the American Council On Exercise (ACE) found that indoor spinning on a regular spin bike can keep you at around 75-95% of your maximum heart rate, which is more than adequate for a triathlete to build cardiovascular fitness. Of course, a big part of this heart rate boost could be the heat of an indoor spin room, the peer pressure of spinning classmates, and the motivation of an instructor barking orders in your face. However, as you’ve just learned, spinning tends to use primarily your hamstring muscles because of that fly-wheel, which A) means more help from the spin bike and fewer overall calories burned or muscles strengthened and B) you using far different muscle groups in a different way compared to what you’d experience with outdoor cycling.
Cycling: As you know if you’re a serious triathlete or cyclist, you can easily get your heart rate as high and higher as those in a spin class. But if you’re new to the sport and have a hard time pedaling that fast while balancing the bike, navigating, and not having the motivation of a crowd and an instructor, you may find it easier to build skills on the bike, and then build your cardiovascular fitness in a spin class. But in contrast to a spin bike, you use your glutes, hamstrings, quadriceps, shins and calves more when you’re on a bike outside – so your muscular fitness will likely be higher (as long as you don’t spend much of your time “cruising”). But once again, you need to be working hard enough to hit those muscles with adequate force to make them stronger and to burn significant calories, and some people just have a hardtime riding a bike that hard unless they’re racing.
Fitness Summary: The average triathlete, and especially the beginner triathlete, can get pretty fit in a spin class. But they should neglect outdoor riding skills, and if you can get your heart rate high with outdoor rides, you’ll be better served keeping things on the road, or throwing your tri or road bike on an indoor trainer (which doesn’t have a fly wheel like a spin bike does).
Spinning vs. Cycling – Perceived Difficulty
Spinning: When you’re riding a bike indoors, spinning can get boring fast, and it can also use the same muscles over and over again (no ascents and no descents). This can certainly make spinning seem more difficult than cycling. But the pounding music and group/instructor motivation can help with this. Plus, it should be noted that a spin class can make time go by much faster compared to just throwing your bike on an indoor trainer.
Cycling: Unless you’re in a race or training with a fast group, cycling goes by much faster and generally feels much easier from an effort standpoint compared to a spin class. But as you take your cycling to the next level, there are technical skills required that can quickly make cycling become more difficult than spinning.
Perceived Difficulty Summary: For the most part, doing anything indoors, whether running, rowing or cycling, will feel harder, and a big part of that is the boredom component. But the better a cyclist you becoming, the more “difficult” you’ll be able to make your cycling sessions.
Spinning vs. Cycling Summary:
You’re going to get a great workout with both spinning and cycling. But if you’re a triathlete, you’re going to want to be primarily training the muscles you’ll be using during the race, and also getting used to handling your triathlon or road bike. Especially if you’re a beginnertriathlete, a spin class is going to give you great motivation and improve your fitness – but unless you’re just doing spin classes because you enjoy the heck out of them – you’ll get more bang for your triathlete buck by riding your bike outdoors.
Ben Greenfield is the Renaissance man of the sport of triathlon.
He's a fast triathlete, a coach, a personal trainer, and much more more.