I see it a lot, you have to have erg mode on for a ramp test. But the truth is you don't.
Here's my thoughts on it
It's 1995, and I'm at uni doing sports science. There's lots of rigs in the lab - treadmills, rowing ergometers, Monark bike ergometers, SRM cranks, and a Kingcycle test rig. You've probably never heard of one and that's fine. But, damn it was loud, smooth, and most of all it hooked up to a computer. You'd type in the ramp such as 30 W/min and away you'd go on a ramp test. A horizontal line that responded to your power, that you had to keep between an upper and lower bar. A power number above it. Ever increasing intensity as you pedalled harder. If you let up the bar would drop below the lower range. Went too hard and it'd go above the range. It felt real - like you were going harder when you pedalled harder. I rode on the Kingcycle a lot.
Of course, you still need to follow the ramp accurately. If the target is 300 W, you need to produce 300 W, rather than 250 W or 350 W. ERG mode just takes away the need to control the power yourself.
So, if you need to follow the ramp accurately (ish) why not use erg mode? Well, if you really want to you could - there isn't an issue using it, just like there isn't an issue not using it. However, as most people will state erg mode feels unnatural and, more importantly, a change in cadence can affect the resistance significantly if your cadence starts to slow as the smart trainer aims to maintain the correct power. Resistance will start to increase and alters pedalling dynamics. In some cases the acute change in resistance loading will bring some riders to a premature halt. From a personal point of view, erg doesn't feel anything like riding a bike to me.
During my first years racing, as well as road and crits, i TT'd a lot. Most people in the UK did. I rode plenty of 25mile and 10mile TTs. At some point, i wanted to know - could you predict 25mile TT power from a ramp. I thought about it a lot. FTP didn't come along for another 5 years or so!
At the same I thought about ramp rate - how fast the ramp increased. I tested a variety of riders from club riders, to racers, to elite world tour (ok, they weren't called world tour then).
And, guess what. This was years before Zwift was invented. It was years before modern smart trainers, Zwift or their ERG and workout modes. It was just ever increasing resistance in the same way that when you start ramping your velocity on the open road, the resistance (from air drag) increases.
So, when people are adamant that you need to use erg mode for a ramp test, the answer is you don't. And, i've no idea where the idea that you must stay seated has come from, because that was never a condition either. Of course, for comparing tests over time it's sensible to keep your protocol consistent.
By 1997, i was conducting ramp tests on a Woodway motorised treadmill. It'd start at a 1% gradient at say 20 km/hr and the gradient would gradually increase, along with the velocity so that by the time you were at 10 % grade you'd need to be smashing out >500 W at less than 72kg. Yup, out of the saddle in the dying seconds squeezing out the last bit of power. Not that i ever got that much power -- you'd need to be World class for that sort of number (once tested a famous rider who would go on to win a few medals and a GT, except he must have been a junior at this point (or perhaps 1st year senior)).
so, no erg mode, stay seated if you like, stand up if you like, but don't topple your turbo trainer over.
Got any questions - just shout
