Heart rate zone, sweet spot training

Hi. I’m new on Zwift, 64 years old, fairly new to cycling. I signed up for the Build me up program and did the Ramp test first. New FTP: 225. I chose to lower it to 212 for the Build me up program. To day, in phase two, doing four 10 min intervals at 190 watts, my heart rate reached appr 92% of Max hr during the last half of the last 10 min interval. From what I’ve read it’s supposed to be in the range 75-85% (the first three 10 min intervals came within that range, rising progressivly off course). Anybody got any advice? Should I ignore this or should I lower my FTP more. Thanks

Welcome to the Forums, Jan-Erik.

First of all, I’m not a medical professional, coach or certified in any way in this field, so feel free to ignore this.

I don’t think there’s anything to worry about particularly in those numbers. If you are not used to training for extended periods at that intensity, it’s not unusual to see cardiac drift, as your body works harder to keep going in the latter stages of the workout. If you had hit 92% of your max heart rate in the first intervals, it would be more of a concern.

If a rider is dehydrated or generally tired, the cardiac drift could be expected to occur earlier.

Also, are you riding with sufficient ventilation?


Thanks Roule, happy to be a part of the Zwift community. I agree with you, but thought I might post it here, get a respons, some advise. I’ve mostly been running up until now, and I’m quite used to hard training. Cycling and going into spesific training programs like the ones on Zwift feels different for some reason, and I just want to get the most out of my efforts. I think you’ve got a good point mentioning using a fan. I haven’t gotten one yet. I open a window in my basement to get the temperature down, but I guess it’s not optimal. Still, I live in Norway, and right now there’s minus 5 degrees Celsius outside. :slight_smile:

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the problem is you’re not actually moving through that cold air in ur basement.
when you’re stationary, your body retains much more heat, compared to cycling outdoors.
once you get too hot, your heart rate goes up.
so defo get a fan asap, it makes quite a big difference, see here for more info: Do You Really Need A Fan For Indoor Training? - YouTube

also when you did your ramp test, did you stay seated?
my FTP from ramp test is always higher than what I can actually do in a 20/60min max effort attempt so it’s not a perfect tool for estimating it, especially seems to be the case if you are more of a sprinter than an endurance rider.

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Hi Ben. Appreciate your input. Getting a fan tomorrow. Been told the same about the ramp test, and that’s why I lowered my FTP for the Build me up program. Might even consider to go lower as the stages get tougher. The ramp test: I was seated all the time. Running: yes, I mostly ran 3 to 5 km runs last ten years, and 4x4 sessions etc. Cycling will hopefully build my endurance through winter.

Don’t just stop at 1 fan! I’ve got 2 20” floor fans (1 in front and 1 behind) and a 12” desk fan on a table next to me pointed at my face.

I’m almost finished the build me up plan, enjoy it!

Sounds optimal, David. Will consider more than one. Thanks. :+1:

You might be able to also help me with this, David: to day I found that last week’s last workout on Build me up is locked. I didn’t have time to do it yesterday so I saved it for to day or tomorrow, but now it seems I have to move on to the next workout. What about people who get sick or have to travel abroad? Not much flexibility here if I can’t unlock the workout outside the week plan.

There isn’t too much flexibility at all. You can do the weeks workouts in whatever order you want (this wasn’t always the case), but the plan is broken up into fixed weeks and if you don’t do a workout that week you miss it. There have been requests about pausing a plan to allow for vacations/illness, but nothing as of yet.

If you just want to do the workout I think they are available in the workouts as single workouts. If you do it this way you won’t be credited with having done it in the plan view. Personally I’ve missed 2 during the course of this plan (1 due to timing and 1 to me being too fatigued) and now I’m near the end I’m not too concerned about it.

Thanks, David. I’ll check out the workout section and see if I can find it there. As there is a progression and an intention behind each stage in the Build me up plan, I would prefer to do them all.