It’s that time of year again. The weather has turned, legs are hidden away and covered in hair again, the roads seem wet even when it hasn’t rained for a few days and every ride ends up being a dawn or dusk one. This is the time when you start to think, should I be riding indoors or outdoors? There are arguments for and against both, it’s all very dependant on personal preference, goals and other individual factors. Let’s dive into the pros and cons of each.

Indoors 

Be it riding on the turbo, rollers or specific indoor bike, riding indoors is certainly a very time efficient and easy way of ‘getting it done’. Gone are the days of nothing but a blank wall to look at while wishing you could be socialising with friends again. Thanks to various indoor training apps and chat apps etc, you can still do ‘social’ rides indoors. It also means there is a lot less time spent getting kitted up beforehand or bike/kit cleaning afterwards. Your chain and other drivetrain components won’t be getting battered by the elements and you never have to worry about that one patch of ice that you will somehow hit (every year so far I’ve managed that). 

A big benefit of indoor training is that it is very specific. You can ride at exactly the numbers that you need to with little or no deviation. Riding outdoors, you may have to sprint out from a junction, or push just that little bit too hard to get over a particularly steep climb. Indoors it’s all very controlled. There can be disadvantages to this though, as in races, especially road, pace varies dramatically and an ability to deal with changes in intensity is vital. 

Another question is “to ERG or not to ERG”. It certainly makes the session easier to follow, but there is some debate as to whether it produces a slightly false resistance when compared to riding on the road. On the road you are overcoming gravity (when riding up hill), friction/rolling resistance, and air resistance. On the turbo, you only ever fight friction. This can also mean that you inadvertently get more used to riding in a purely comfortable position rather than in a position which provides a balance of comfort and aerodynamics. 

In my dissertation, I investigated the effect of gradients on muscle activity. In races, the end result is often heavily dictated by performance on climbs. In my study I found that when riding at the same high intensity on different simulated gradients, muscle activity was significantly different in the hamstrings (bicep femoris), calf muscle (gastrocnemius medialis) and quadriceps (Vastus medialis). It could be suggested that long periods of riding indoors, on essentially a level gradient, could result in reduced performance or greater feelings of fatigue when producing efforts up gradients. You can read the full study here.

An interesting benefit of indoor training, is heat adaptation. Normally we’d think this is something beneficial for racing in hotter climates. But heat adaptation has its benefits for those looking to perform better everywhere. Becoming more heat adapted increases blood plasma, which helps improve sweat rate and our capacity to lose heat. It also has been found to increase the levels of haemoglobin in the blood. Essentially our blood can become better at carrying and transporting more oxygen to the working muscles. The result of this is reduced time to exhaustion, higher maximal aerobic power, higher sustainable threshold power, and improve recovery time from efforts. So although heat adaptation and the associated increased sweat rate might mean riding out on the road you have to get used to layering up and drinking a bit more, you may also experience some tangible performance gains.

One undisputable benefit of riding indoors however is the time efficiency. It is a lot quicker and simpler to get the work done compared with doing an equivalent session on the road. If time is of the essence, the turbo is nearly always king!

Outdoors

So if indoors is so efficient and useful for training, why should we consider outdoors?

Firstly, technical skills. You can’t learn bike handling or bunch riding skills when riding on the turbo or rollers. Pretty much any cycling goal be that a race, sportive or a strava segment can be improved with better bike handling skills. Cornering, descending, and saving more energy when riding in the bunch are vital skills to learn and can only be done so outdoors (track for bunch handling skills too). So getting out and riding outdoors is the best way to hone these additional skills which will still help you improve as a rider and perform better.

Another element of riding outdoors that isn’t the same as indoors is the variability of the pace. When we ride indoors we tend to keep to a number that fluctuates maybe 10 watts either side of the target. This is good for staying in the correct zone, but at the same time if we are doing events out on the road then it is important that we can deal with variable pacing. Be that from the terrain changing rapidly, a quick change of pace in the bunch, or the wind changing direction. Which takes us onto the next thing, gradient! In the study I did that I mentioned earlier, it was found that changing the gradient that we cycle on does impact our muscle activity during the pedal stroke. Several of the main locomotor muscles in the legs changed in their muscle activity readings as well as firing patterns as the gradients increased. So if you feel that riding up a hill feels different than on the flats even for the same power, that’s because it does! Although we can do gradients indoors with gradient simulators, it is far easier and cheaper to ride out on the roads on some climbs. Riding solely indoors won’t help you to fully maximise your potential performance on inclines, so it’s well worth including them on your outdoor rides. Especially as climbs often make a large difference to the result of a race or time of a goal event.

Something else to consider is being used to the weather that you may experience during your event. Yes we all love a sunny and warm day out on the bike and that’s the ideal scenario. But there are plenty of occasions where our race, sportive, 100mile ride or training camp gets afflicted by colder weather, wind and rain. If we have been used to training in these conditions over the winter then we likely know how best to kit up for the conditions. It’s very easy to be too cold or too warm and for that to affect your performance significantly. Another benefit is the psychological aspect of things. Often on the start line of a race when it’s raining there will be two predominant mindsets, “Let’s be having ya!”, and “I don’t like the cold and wet”. The first mindset often seems to perform better and can be reinforced if we’ve experienced the conditions, know we are well prepared for them, and that they can’t affect us. Not so much mind over body, but the two working together.

Outdoors is also the best way to keep social, even if it’s about sharing the suffering. Some of my favourite rides have been in horrendous conditions where I’ve seriously considered phoning for a pickup! I would say though, that if there’s even a slim chance of it being icy, don’t risk it. You’ll have to ride cautiously so won’t be getting any decent training done and one small patch of ice is enough to derail you completely. On these days, the risks outweigh the benefits by a very big margin.

So, to summarise: there are pros and cons to both indoors and outdoors. A combination of the two is generally best but this will be different for different people. Personal preference is another factor; some people can manage 4 hours indoors, some can’t. There’s no point burning out all of your motivation 3 months before even the early season races start! Make sure you’re well equipped for whichever ride you do. Indoors, you can at least get off the bike to fill up a bottle or grab snack easily. Outdoors it’s not so easy to obtain something you’ve forgotten once you’re 50k from home! The biggest thing is, enjoy what you’re doing. That’s the main reason any of us should be riding a bike.