字幕列表 影片播放 列印英文字幕 (upbeat energetic music) - Welcome back to the Triathlon Training Explained show, powered by TrainingPeaks, now if from time to time you are riding indoors, perhaps on a Turbo Trainer as I am today, then you will have quite likely at some point complained that it feels somewhat hard, or maybe considerably harder than when you ride outdoors. Your heart rate's higher, your power's lower, your FTP maybe feels a bit out of reach, what is going on, well you'll be pleased to know that you are definitely not alone. Today, I'm gonna be exploring that conundrum and be looking at how it happens and what you can do about it. (upbeat energetic music) Now, I must admit there have been times that I've jumped on the indoor trainer and I've wondered, what the heck is going in with my legs? And it can really play with your head because effort just seems so much harder to achieve. Sometimes, impossible whereas normally you're knocking 'em out of the park when you're outside on the road. So, what do we think is happening? Well, I've been out and I've asked you just that. Now, why is it harder, indoor training? - Because you don't get any rest. You have to keep going all the time. You're not able to glide and you have to keep it in the zone or rate area which is much more difficult when you're on the bike. - The thing I find hard about indoor training is that there's no distractions, there's no changing gears, there's no steering, there's no needing to be aware of traffic. So, you really have to focus on the pain, and how much it hurts. - I think it's because of the heat and you don't have the wind coming against you cooling you down, so you can easily overheat which can make you feel like you are putting in much more effort than you actually are. - It's a definite love/hate relationship with the indoor trainer, and it makes training a lot harder. There's no free wheeling, coasting, sitting behind people, there's constant tension on the chain as you're pushing through the session. (upbeat energetic music) - Well, there are some very good theories there, but let's see what the science says. Now, one theory is that it's due to a reduced cooling effect. See, the human body has quite a small and finite range it can efficiently operate in, and that's between 36.5 and 37.5 degrees Celsius, and this is what's considered our normal body temperature. Now, if we go just a fraction above that we can start to feel a little bit off and actually, our training like cycling might start to feel a bit more laboured. If we just go about three degrees Celsius above maybe to around 40 degrees Celsius we can really start to feel quite bad, and actually we can start to experience the onset of hyperthermia. Now, obviously when we're cycling indoors we are stationary, but our bodies are still creating vast amounts of this energy to power our legs and keep things working. So, this is where things get really interesting because the cells that are in our body actually get their energy from food and then creating and using that through ATP molecules, and they are then used to make our body work and make our legs work, and we have to cycle. Through this whole conversion, it's actually only an overall efficiency of around 25% that's actually used to make our legs work. The other 75% is, wait for it, is lost through heat. So, if you take a cyclist cruising along outside at about 30 k.p.h. Their experience, a nice wind, a nice breeze, a bit of headwind. That's equivalent of a big big ol' fan around 30 k.p.h or perhaps even more depending on the conditions. When we're riding inside, that headwind that breeze, it's all gone. So, you can start to understand how the body starts to feel the effects of this heat, and it starts to respond in a few ways. Firstly, we have a slight increase in our heart rate. Secondly, the blood starts to shunt, and move away from our muscles in an attempt to dissipate the heat. So, it goes towards our skin to try to relieve that heat out of our body, but through doing so it's obviously taking oxygen away from our muscles which then might start to experience a slight loss in power. Another way it tries to dissipate the heat is through sweat, and in doing so we can end up feeling slightly more dehydrated and again, a loss in performance. Also, as temperatures really rise then our head and our brain literally cook, meaning it leads to a decrease in motivation, concentration, and perhaps even lowering our pain threshold. But, of course we all know that, that's why we use a fan. A fan is there to essentially recreate the wind to try to keep us cool, to wick the sweat away from our skin, and stop us from overheating. What I would say, is that I know from experience that I am pretty much always dripping with sweat when I get off an indoor training session, despite having a fan. So, perhaps it does contribute in some way to making indoor training harder. Now, another theory is that it's due to being in a fixed position. (upbeat energetic music) So, without the ability to actually move the bike, we're causing ourselves to use more isolated muscles, that perhaps aren't used to working quite so hard. When we ride outside on the road, we're able to shift our body weight around, get a powerful bike, move the bike around. In turn, we can start using more muscle groups, even our upper body, our core, as well as obviously our legs to really help produce as much power as possible, and actually, through doing that we can allow some muscles to recover and rest, whilst others are working to overall help to produce as much power as possible. Another thing athletes do complain about is that some muscles, or certain areas of muscles might hurt. Such as, adductors coming up the inside of the leg. That's a real classic one because when we're riding outdoors we don't tend to utilise and use those muscles quite so much. They seem to get quite a hammering when we're riding indoors and that can really contribute to a slight loss in power. What I would say is that, with time when you're riding indoors, you will start to train those muscles up, condition them, get better at using them, and hopefully start to find it's less slightly of an effort. (upbeat energetic music) The indoor trainer also has the ability to suck the life out of even the most motivated of athletes. So, if you're riding indoors, maybe in your garage, your dark garage next to your lawn mower, and a bunch of tools; Let's be honest, that is nowhere near as motivating as riding outside on the road, on a clear sunny day. So, if you're not as motivated that is going to contribute to a loss in power. So, what I would say is for indoor training try to tailor your sessions specifically for indoor training, keep them engaging keep them interesting, keep that body guessing. Try to make them slightly shorter, more intense. Maybe don't do quite so many of the longer rides indoors, otherwise you are just going to mentally burn yourself out. On that note, also things like Zwift, and other virtual indoor training platforms are great for keeping you interested, and engaged in indoor training. (upbeat energetic music) But, the big reason I believe comes from the indoor trainer itself, or at least from some indoor trainers. See, when you're cycling outside on the road and you stop peddling, you coast, you just keep on going, But when you're inside on an indoor trainer, and you stop cycling, you pretty much come to a stop within seconds, or at least, on some indoor trainers. So, what's happening is when you're outside you have the momentum from your own body weight, your bike weight, and that just keeps you going so you can free wheel, and you can come off the gas and coast. Whereas, inside on an indoor trainer, you have a flywheel that's attached to the resistance unit, and what that flywheel tries to do is, it tries to replicate that feeling of riding outside on the road. But, from experience, and we all know this, It doesn't really do it that well. So, what you're having to do is work harder to try and maintain that momentum. Because of this flywheel, it also changes the way that we apply force throughout the peddle strikes. So, when we're cycling outside on the road you may think that you're applying force evenly and smoothly throughout the whole peddle strike, but in actual fact what you're probably doing is applying force through the down stroke, and that is also aiding the recovery of the other leg back up to the top of the stroke, and vice versa. This all changes slightly when we start to go up a hill, because we need to apply force throughout the whole peddle strike to maintain that momentum, otherwise we'll either fall off our bike or fall back down the hill, and that is very similar to when we are riding on an indoor trainer due to that flywheel, and that inertia that we've got to overcome on the flywheel, and try to maintain that momentum. Now, all of these factors are contributing to what is making it harder, and considerably harder than when we'd ride out on the road where we've got minimal resistance from tyres and from wind for instance. But, fortunately these issues are becoming less and less, due to advances in the flywheels. We've got bigger flywheels on the dumb trainers but most importantly, it's due to these smart trainers, and direct drive trainers as I'm using today.