Climbing is, for a lot of us, the epitome of what cycling is: from getting a PB up your local climbing segment, to sportives across mountain ranges, to watching the likes of Pogačar dance up them at a sickening pace. There’s something very different about going full gas up a climb to going full gas on the flat; it feels like a different challenge and sometimes quite a bit harder. Is it because of the fact you get less speed for the same effort and the psychological effect that has? Is it the constant force of gravity always putting up a relentless fight? Or are there other factors that contribute to climbing feeling harder than being on the flats?
Having personally got a Wahoo KICKR climb gradient simulator for training during bad weather, I was curious as, when the gradient was set at a higher level, the same power levels felt harder than when the bike was set to the flats. I decided to do my undergraduate dissertation on investigating the effects of simulated gradients on muscle activation. (Full dissertation study)
6 participants cycled at 75% of MAP for 2 minutes at gradients of 0, 7, 14 and 20% incline. During this test, the EMG (electromyography) levels in a number of leg muscles was measured to determine if certain muscles worked more or less on different gradients. The results showed that there was a statistically significant increase in muscle activity in the gastrocnemius medialis (GM) and bicep femoris (BF), with a significant decrease of activity in the vastus medialis (VM). There were also changes in muscle activity in other muscles that, although were not deemed statistically significant, do present a practical significance given the percentages involved. The reason for these changes could be due to several factors. Firstly, when climbing up steeper gradients, we tend to close our hip angle so as to keep weight distributed evenly over both the front and rear wheels. Additionally, as the gradient increases, saddle angle changes and can require some muscular effort to maintain position.
So what does this mean for us? Based on the results of this study, it can be suggested that training on gradients regularly could improve performance on them. Although power levels over given periods of time can be improved from training on the flats or on the turbo with no gradient, training on a gradient can help significantly with rate of perceived exertion. There’s a good reason that, even after plenty of time spent on the turbo at higher intensities, going out on the roads and hitting the climbs can feel that bit harder. It’s because we potentially haven’t been using the same muscles in the same way, so introducing that new stress does feel like more.
The takeaway: it looks like there are genuine benefits to training on gradients. You can train on gradients by either riding them outdoors, or using an indoor gradient simulator.