Hi, iv recently got myself a pair of favero dual pedals. It’s my first time riding with power outside and is it just me or does it feel much easier than being inside?
Inside 280-300 watts starts to feel tough, ftp is around 290. But outdoors I feel like I can hold 300watts relatively easy not getting too out of breath. Also my cadence seems to be about 10rpm higher outside which seems odd as I have shorter cranks on the wattbike
Yes, this is very common. There are several contributing factors, but cooling is often touted as the largest. If you’re riding 300w at 25mph on a road, you experience wind flow at 25 mph across your entire body. To recreate that scenario inside, you would literally have to ride in a wind tunnel. Most people use one or two fans for their indoor training, and even if they’re high speed fans like the “Wahoo Headwind” or “Vacmaster Airmover”, they’re a far cry from a wind tunnel.
The gross efficiency of cycling is 20-24%, which means about 76-80% of all the energy you use during riding is lost as heat. If that heat is not allowed to dissipate efficiently due to a hot environment and/or a lack of air flow, your RPE and heart rate will rise significantly across the entire intensity spectrum. Adding to that, the stronger you are, the more this will affect you since gross efficiency drops exponentially as power rises.
Across studies, it seems that power output is decreased to the tune of 5-15% inside as compared to outside. Personally, I use 4 Vacmaster Airmover fans inside, all running at a wind speed of 50kph and pointing directly at me. Despite my best efforts to cool myself off, I’ve found that across the power curve, I consistently perform about 10% worse inside as compared to outside. I’ve come to that conclusion based on repeated 20 minute tests, long sweet spot efforts, and power at zone 2 heart rate and RPE. In other words, if I can do 20 minutes at 330 watts inside, I can expect to do about 360 watts for the same duration outside.
There are other factors than cooling which may negatively impact performance inside such as motivation and poor trainer quality (lack of inertia, etc). It’s also far easier mismanage fuelling and hydration when there is no fear of bonking – “The fridge is literally 10 feet away, I don’t need a gel right now”. However, as we know, we don’t perform like cars because we don’t have combustion engines. We simply cannot produce the same power with a half tank of gas. Keeping topped up on carbohydrates is one of the most important factors to consider for performance both inside and outside.
Also, ymmv, but riding outside gives me a much bigger adrenaline hit. I find it’s just more fun + more distractions → less painful for the same output → I can hit bigger numbers for longer.
Cooling could be a major factor, but when it’s 85F outside and 65F in my basement with a strong fan, I still do better outside. There are so many more distractions so it’s way less tedious than on a trainer, and actually propelling yourself faster and further is motivating.
Perhaps unusually, but I can sustain higher power numbers indoors (if erg mode is on) for efforts of 10+ minutes than I can outdoors. Maybe having it right on my physical limit with no variation helps me ride the line almost but not quite blowing up. Have tested it’s not a PM difference (same bike + pedals dual recording).
Maybe this is similar to being able to push harder in a race than in training. When on a trainer in ERG mode, you sort of have no choice but to just do the power. Giving up and letting the trainer grind to a halt just feels like such a disappointment that gritting your teeth and suffering seems more manageable. On a solo ride outside, the feeling of defeat is not nearly as palpable as you just sort of slow down if you fail an interval power target. However, on a group ride or in a race, the feeling of dropping the wheel is even worse than grinding to a halt on the trainer, and we therefore cling on at Vo2 breathing for much longer than we thought possible. Maybe there’s something in that, maybe not.
I have exactly the same problem. But what I have realized is that my indor power was lower/harder to sustain in ERG mode. Once I started to do my workouts without ERG mode, my indor power incresed. Check this out! Many people have the same problem with ERG mode. Also, I heard that heavier flying wheels also help with keeping the power indoor close to the outdoor power.
I don’t have erg mode and find it harder to maintain same power outside. I have a left Stages PM on indoor bike and a spider PM on my MTB, but I also had same Stages PM on a previous MTB and same thing applied. I think it has something to do with not having to engage balancing muscles but that is only a guess