I appreciate that Intervals incorporates other work that I do in my day to day life - mostly walking with my wife but how does it calculate load? I would assume its done based on heart rate.
Which then leads me to a couple other questions.
Why isn’t biking done based on load? I know we calculate based on FTP.
And how do you know when your FTP has changed? I ride almost exclusively single power rides on Zwift in Tempus Fugit (flat) so it never really has an opportunity to evaluate my FTP.
Yes. Load calculations based on HR where no power meter is used. I think!
Cycling load is calculated based on FTP when a PM is used. One hour at FTP = a load of 100. These calculations are limited though, but are pretty much the best we have right now. In a 5 hour ride at 200 watts the load for the first hour is calculated the same as the load for the last hour even though there is likely a much larger metabolic cost over the last hour.
By doing an FTP test. You might also keep an eye on your Pw:Hr ratio and maybe see increases in efficiency there.
Power is an ‘external work’ number and thus very consistent. If you push the pedals with a certain power today, the number will be the same as tomorrow or next week.
Heartrate is an ‘internal work’ number and very dependent on a number of factors like recovery, sleep, heat, hydration,… If you push the pedals with a certain HR today, the result as ‘work done’ can be quit different from tomorrow or next week.
Is Power better then HR? In some cases like High Intensity bouts, yes. Short bouts of intensity will almost not show on HR data while they can certainly influence your remaining capacity somewhat further in the ride. With power, those bouts will clearly show and they will have impact on load.
Should we discard HR then? Not at all! The combination of HR and Power numbers gives more insight. If you normally ride about 150W at a HR of 130bpm and todays numbers show that your HR is 140bpm for the same 150W power, then something is going on. You might be overheated, dehydrated, fatigued, getting sick… These discrepancies are sort of an alarm-bell to tell you that something isn’t going quit right.
In Intervals, you can select what number you want to use for load calculation, power, HR or pace.
Power load is referenced to FTP, HR load to LTHR, pace load to Threshold Pace.
If your routine is walk and bike in the lower intensity zones for health reasons, you could set both Ride and Run(walk) to prioritize HR as load calculation and you will get more consistent numbers when comparing the loads between activities.
But if you do HIT work on the bike, you will be better of by using Power for the bike and dialing in your zones so that HR and Power zones are better matching.
To know which parameter is used for your activities, check the settings page and the Load calculation setting for each category. Intervals will use the first one on that list that is available in your activity file to calculate load.
RPE is another “tool” you can use to measure effort. Similar to HR, it’s a subjective measurement. If today you did 150W and it felt easier than normal, chances are you’re feeling good or better than normal. Likewise, if it felt harder than normal then you a probably feeling a little weak.
This can be pair with HR and Power to triangulate the effort. If feel was poor, and HR was higher, the chances are something is off.
If power and RPE is as expected, but HR is off, it could be something, but probably not that bad.
“By doing an FTP test.”
Doing an FTP test is significantly disruptive to a normal week’s training load. I’d prefer not to do FTP tests weekly or monthly.
thanks for the thoughtful reply - seems like we are who are number geeks could figure out a way to signal to the user when a material consistent change has occurred.
For example average HR decreased at same power levels over a period of weeks could indicate that a user’s FTP has increased.
What are your reasons for riding?
If you progress your threshold intensity workouts (Z4), you’ll be doing 30-60 minutes time in zone as you progress, with some recovery mixed in. By the end of a 12-week block, your threshold is either higher or you can ride the same level (power) for longer.
“What are your reasons for riding?”
I don’t understand that question in this context.
“By the end of a 12-week block”
Is that the answer? FTP test every 12 weeks?
If you ride like this, unless very new to structured training, don’t expect material gains in FTP. You need to periodise your training over time and manipulate load and intensity to see increased in FTP (and other associated performance metrics).
I would like to piggyback on this question, given the appropriate thread topic.
I am doing soccer practice at my soccer clubs on two days every week (1h each). So in intervals, I am usually putting in a Load 50 for this, or maybe Load 75, if it was really exhausting. Is this about right, or too high, low ? Opinions ?
You would need to do a running lthr test and then wear a heart rate monitor while playing to have any sort of useful numbers.
Your goals should determine how you should be training, if you have any desire for performance in mind. Setting up zones/levels are then required to help guide the training, so you can maximise the gains.
Yes and/or No.
It depends what you’re training for.
Extending time in zone won’t require testing as often.
