FTP vs. Lactate Threshold

Quoted post said:

Originally Posted by fireman7875 [IMG]/img/forum/go_quote.gif[/IMG]

With respect to HR, is FTP the same as lactate threshold? In other words, will my HR at FTP be the same as my HR at LT?

I don't have have a power meter to train with so I wondered if there was a way to figure my FTP using HR.

thanks,
Brian

The intensity (power) at LT is a bit lower than FTP and your steady state HR for extended periods at LT should be a few beats lower on average than HR at FTP as well. It's confusing in part because LT is defined different ways per different testing protocols and even the scientific studies have to carefully outline how they're using the term and HR has a fair amount of day to day and situational variability so depending on things like hydration, recovery even emotional state HR can vary for the same power and or blood lactate levels. But yes in general on a good day going all out for roughly an hour the intensity you can maintain is a bit higher than the common ways to identify LT (OBLA, MLSS, exponential break point, rise above baseline, etc.).

A good way to estimate HR associated with FTP (understanding the day to day variability part) is to do an all out 30 minute effort but to account for HR lag take the average HR for the final 20 minutes as an estimate of HR at FTP. HR at LT if that's what you're after for training will be a few beats lower in general and the effort shouldn't be quite so brutal but still very focused.

And when using it to guide training you should also account for that lag in HR. IOW if you do something like a 20 to 30 minute LT interval based on HR don't expect to see your target number for the first five or six minutes, if you do get right up to your target LT or FTP HR very quickly you're almost certainly working a lot harder and may have to back way off to finish extended efforts which is generally not the idea.

HR also continues to drift upwards during steady power efforts so even if paced very well your HR may drift a handful of beats above your ideal LT/FTP targets in the closing minutes of longer hard efforts, that doesn't generally mean you should back off on intensity, just account for the expected drift that happens in most situations.

-Dave

Thanks, Dave! So would it be fair to say that one's FTP is is more like a TT effort and is not a zone in which you should spend a great deal of your training time?

Brian

Quoted post said:

Originally Posted by fireman7875 [IMG]/img/forum/go_quote.gif[/IMG]

Thanks, Dave! So would it be fair to say that one's FTP is is more like a TT effort and is not a zone in which you should spend a great deal of your training time?

Brian

That would be more than fair as the gold standard definition of FTP is your best power for a well ridden 40 km TT ridden on an ideal day which includes sufficient freshness and high levels of motivation as in an actual race.

But that's FTP as a singular power number or intensity. Actual training to improve FTP (or LT) usually includes a lot of work below that level and even focused L4 (Threshold focused training level) training is often done at 90% to 95% of a rider's FTP. IOW you don't have to nor necessarily even want to do too much training at 100% of FTP as it can be a burnout track and you get almost all the benefit by backing down a bit and can do a lot more of that kind of work over time.

FWIW, one way to look at this is that we tend to be able to do a lot more work focused on raising FTP by working out at intensities closer to LT (depending on exactly what method you use to define LT) and do a lot of our Tempo work a little easier yet so again we can do a lot of that work without destroying ourselves.

-Dave

Hey Brian, you're spot on! FTP is more of a benchmark than a training zone. While it's good to know, most of your training should focus on developing your aerobic system and lactate threshold. Happy pedaling!