Having recently started introducing high intensity intervals into my training plan, I’ve hit a weird issue with the turbo trainer. I’m meant to be aiming for intervals of 4 mins @ 170bpm, but I really struggle to get my HR above about 150bpm before my legs blow up. Thing is, it’s not like I feel particularly tired or anything & I could quite happily go out for a fast ride and I bet I could get my HR above that in no time. There’s something about being on the turbo trainer that’s causing me a problem.

I’m finding I need to put the bike in a big gear on the turbo to get my heart rate above 130 ish, but then my legs get really tired by the time I hit about 150. I’m not massively out of breath or anything, just tired legs because of the big gear I’m trying to push. Problem is, if I drop the gear then my HR drops down even lower, even with a high cadence. One issue might be that I can’t get out of the saddle on the turbo as the bike just lifts off the roller, but I think it’s more than that.

Any thoughts? Cheers.

You need to warm up for a while, then put it into a medium gear then hammer for 20 secs, up a gear, hammer again, up a gear and hammer again.
back down 3 gears and repeat. do this for 5 minutes and your heart rate will be well up there.
Then you can train 😆

I had exactly the same issue with my turbo trainer. It was an old fan type (horrendously noisy!), I came to the conclusion that I was a cycling god there wasn’t enough friction/resistance generated, I don’t bother with it any more.

If its a magnetic trainer it probably can’t generate enough resistance.

Try a fluid trainer of some sort, you will definitely get to your target heart rate.

Sounds lack a lack of warm up. I find it easier to reach the desired higher rates after 1/2 hour.

And please don’t be offended by this, but have you selected a programe your not quite ready for?

Just had a session today, with 3 x 9 minutes at 165 but found I was having to ease off to stay that low which suggests I may have picked one that is a bit too easy?

Mark, as you know I’ve borrowed a turbo to stop the rot. Mine uses a fan, and I was surprised how little resistance there is. At my normal cadence even in top in road gearing my heart rate isn’t in the cardiovascular training zone, so playing at intervals if I really spin it up I can just hit 160. I’m much less fit than you and prob most posters so it must be technique and high cadence, or more sophisticated trainers?

Thing is with the old style fan trainers, the faster you go, the harder it gets (for obvious reasons) so you have to use a bigger gear.

this is why you use one of the turbo’s that give power readings, heart rate is too suscepable to other factor’s

Tacx flow is the most basic and does the job well

flow – Member
If its a magnetic trainer it probably can’t generate enough resistance.

depends on the model, Tacx Swing (Mag trainer) can definitely generate enough resistance

Coz its the most boring thing on the planet?

If its a cheap magnetic trainer it probably can’t generate enough resistance.

Sorry, thats what I should have said

Coz its the most boring thing on the planet?

And the reason why we are all fitter than you?

I have just got a CycleOps Fluid 2 and the thing is evil, a big change from my Elite Voltaire Mag which was pretty easy even on max resistance and 53/12

you may be pedaling at too low a cadence in too big a big gear

or you’re not fully recovered from previous training

I’ve an Elite Chrono Fluid Elastogel and it’s evil compared to my old mag trainer got to 194bpm on my interval session tonight, almost silent but the heatsink gets dammed hot.

As you’re finding heart rate is a lagging indicator of effort and practically useless for short intervals. In an attempt to get your HR up quickly you are going too hard and blowing up before the end of the interval. It can take my HR 10 mins to rise and stabilise on a 20 min interval even after a good warm up. That’s why more and more people who train seriously and can afford to do so get a power meter.

I suggest you ignore HR and go on perceived effort. For a 4 min interval I guess your training plan is calling for something like 17 or 18 on the Borg scale of perceived exertion (20 being eyeballs out total maximum, 6-7 being very light) Stick a speedo on your back wheel. If you have a fluid trainer or if you make sure you use the same resistance setting on a mag trainer then your speed will correlate to power and as you improve you’ll see yourself going faster and therefore generating more power for the same effort.

Cheers all. The turbo trainer is one of these, so shouldn’t be the problem I think. The chap who does my training plans has suggested I do a slow ramp up of effort & see if that helps. Also reckons I might be putting in too much effort at the start of the interval so my legs blow before HR has a chance to get up to the correct level. Sounds sensible I suppose. The more I train with HR, the more I realise just how unreliable & slow to react it can be. Might have to invest in a TT with power reading if I can’t get along with this one.

Dave, hope you’re recovering well mate. Bet you’re looking forward to getting out again! Oldgit, no offense taken…valid suggestion but I don’t think that’s the issue. Cheers.

@uponthedowns has it spot on, rear wheel speedo and you can pace yourself on the interval. After you have done them a few times you get a feel for the gearing/cadence you need for the type/length of interval.

Cheers, sounds like that’s the most likely issue then. My max HR is 182 (I’ve only ever achieved that in the lab!), so 4 x 4 mins at 170 is a pretty hard session. I’m certainly putting the hammer down when the interval starts, and in a big gear I suppose it’s not surprising my legs fold after a minute or two. Speedo sounds like a good idea, cheers.

Give the rear wheel speedo a good try before you go splashing out on a turbo with power measurement. Like Russell says you will soon get a good feel of the speed to suffering correlation and be able to pace yourself better.

If you go down the power route it would be best to get a Powertap or similar on your bike so you can use it on the road- it will also be more accurate than a turbo power meter.

Edit: from your max HR it definitely sounds like you need to be 17-18 on the Borg scale

cheers. ordering a garmin speed/cadence sensor right now… 🙂

…and googling “Borg scale” 😀

Brilliant you have a Garmin, then use Garmin Connect or Sporttracks to save your sessions. Then you can remind yourself how fast you went on a previous session and also superimpose the same sessions (with a suitable Sportracks plugin) and see how you’re improving.

Thanks yep I use Garmin Connect to upload most rides already. Haven’t used Sporttracks though, will have a look at that.

Pedalhead- my tuppenceworth-
I’d say deffo do a turbo mid-easy warm up for a least 10 mins before doing whatever training plan/interval sessions.

I have a tacx flow with power & cadence. I’m sure the power measurement is not accurrate in absolute terms but it will be relatively between sessions. for a partic gear+ constant cadence you obviously have the equivalent power output as you would for speed+gear.
I can set the Flow to maintain a constant power as it automatically ups the resistance if you drop the cadence- this is really noticeable.
FWIW (I’m not very fit at all) but if I do intervals with the ‘effort’ part trying to maintain at least 120rpm, this gets my HR way up pretty quick.
OR try tabata intervals- if you can’t max out on those by the 8th then you’d need a harder gear/turbo!

Thanks DD. If the speed sensor doesn’t help (sounds like it should), then I think something like a tacx flow might be next on the list.