2 x 20

[Parrott]

My ride to work is the perfect distance for this. How hard are we going here? I find what limits me in a time trial is my legs feel like they are pumping up and lose power, this is after they have been burning for a while, so I try and stay back from that until near the end. With a 2 x20 is the idea to stay on the edge of the burning sensation rather than going right into it? Cant afford a power meter so not going there.

[toolonglegs]

Well I will try and answer until higher powers arrive.

20's are done at varying intensities...depends what you are after 90-95%,100%...105% ftp.I was doing them before I had a power meter and they worked well.Main thing is to be consistent...try and keep constant power during the whole interval...back off going up hill,push downhill.Be steady...easy 10 minutes and do it again...and then again if you want...in the build period they are great.You will need shorter more intense efforts closer to race time.

[Parrott]

Thanks Toolong, just trying to work out what it feels like at functional threshold power if that is what you are supposed to do. I don't think I'm quite as serious/dedicated as alot of you blokes on here, I can learn a bit from those that are though. I guess i'll just do them at a fairly uncomfortable pace and occaisionally bury myself on them.

[snedden9485]

Going off HR, i think somewhere in around the 85 - 90% max is a good starting point.

[lukas]

I do these weekly, but I save them for the trainer. I go off HR, it's usually about 90% of max generally.

I just try to go as hard as I can manage for 20 mins. The last few mins of each interval are tough.. the clock ticks down very slowly! I'm not overly scientific about things, but combined with trainer sessions on another 2 nights per week (soon to be replaced with real rides thanks to daylight savings!), I'm seeing improvements on my longer weekend rides in the hills.

I'd love a power meter to get a bit more precise about things, but can't really justify the expense. Maybe next winter.

[toolonglegs]

They are at about 90% max hr for me...but I don't reach that rate till 5-10 minutes into the interval.Which is why i always go off percieved effort.

[nimm]

What toolong says.

I try and do 2x20 at a sustained level of effort the whole 20 mins (not steady HR). I know from doing this for a bit now (but without a power meter) that my HR settles to mid 150s early on and rises up to high 160 low 170 by the time I end. My max HR is 185 and really if I'm into the 170s I can't keep it there for too long, so in my mind finishing in the low 170s is a good indication i'm holding close to my max achievable power for the 20 mins.

Over time this has definitely increased my power at equivalent HR and I mean it too - a huge difference and I haven't even been doing it that long (plus interruptions for work travel and sickness). That's why I'm keen to get a power meter!

[Parrott]

Thanks fellas sounds like I'm not going hard enough, might have to make myself suffer a bit more than I have been.

[Alex Simmons/RST]

How hard can you ride for an hour?
Do a bit less than that in your intervals.

Trying to go maximal for 20-min each time will wear you down, physically and mentally and you will end up stopping your interval work.

My 20-min power is about 8% higher than my 1-hour power. In speed terms that's about 2% faster. Trying to do that each time I do TTI work would crucify me.

One gains just about the same physiological adaptation stimulus by riding near threshold as they do riding at/above threshold, and by doing them a little under threshold you can do more of them and more frequently and get better overall improvement as a result. But at some stage you have to lift the power - perceived exertion will guide you along that path.

Heart rate response from 20-min and 4-min intervals:

[Parrott]

Thanks Alex. I cant afford a power meter so will continue by percieved effort. Noticed my HR is dropping at the same effort as I get fitter or put another way it is getting alot harder to hold as high a HR as I was a month or 2 ago. It is harder to motivate myself if I'm going to bury myself each time I go out so I'll keep a balance if i can then, thanks.

[tripstobaltimore]

Thanks alex, your advice is always much appreciated.