RFEngineer

I have a power meter, but I probably don't use it, or train with it, properly. It's more of an indicator of how hard I pushed on a ride, at this point. I have noticed my times suffering in the last few weeks due to it getting hotter outside. It seems to me that HR is a better indicator of how hard I can push myself, because the heat has such a great effect on how much power I can sustain. Is this typical, or do I just need to acclimate to the heat? Should I really pace myself to power? This is on a long, sustained climb: 30-40 minutes. Thanks!

noodle soup

In hot weather(Phoenix Summers) HR is better to use as a guide. I'm sure someone will argue this, but they will be wrong.

FlashBazbo

I pace to Power UNLESS my heart rate is higher than usual given my power and cadence numbers. If my HR is elevated (or I'm having trouble making normal power at a given HR), I drink a lot more fluids and pace based on HR until / unless it returns to normal.

woodcraft

IME, power not that different, but HR substantially higher in hot weather.

caloso

I pace to power and feel, regardless of temperature. And yes you need to acclimate.

redlude97

HR being elevated at higher temps is usually due to dehydration affecting HR and not the temp itself necessarily. So acclimate and carry enough water

TrojanHorse

Pace to power! However, as some have noted, your HR doesn't not exactly correspond to your power output in all conditions / at all times, so modulate what you're doing.

Tweak as necessary, says I.

woodcraft

I think of it as pumping more blood to dilated surface blood vessels to cool the body.

robbyville

gregf83 

Perhaps for you but for me my HR is higher at the same power levels in the heat. I can sustain similar power but higher HR when it's hot.
Going up a long hill I mostly just go by RPE, particularly in the 2nd half.

DrIsotope

I note my HR usually elevated around 10bpm if temps are above 90º. HR recovery also slower, and resting HR slightly elevated. I still pace to power, but watch HR as recovery rate is my main check for hydration level.

colombo357

Always pace to power because your HR fluctuation is neither predictable nor linear with temperature changes.

You should know your FTP. Dial it back accordingly on hot days, how much exactly TBD through experimentation. It should be proportionally less to your HR increase.

ddub

HR. Human Resources? JK. Power for me. HR is not really a reliable indicator of your efforts.

macca33

I'd say use your power data, but listen to your HR data, ie, if your HR is noticeably higher than 'normal' for any given power level/effort, then adjust your ride accordingly. I generally have a good idea when I'm crook or fatigued, as my HR will be high (relatively) for the power levels I'm producing.

Remember to drink plenty too!

cheers

gurk700

Power meter = What you are doing
Heart rate monitor = How your body is responding to what you are doing

- You can push the exact same power in 2 different days and your body could respond very differently because you're flatter than usual, you are sleep deprived, you feel friggin' amazing, you are overcaffeinated, you got up from the wrong side of bed.
- Your heart rate could be elevated and you might think you are pushing yourself too hard when you aren't

Basically use both tools for what they are. HR can't provide you with the info PM can and PM can't provide you with the info what HR can.
If you absolutely have one tool, have the PM cause you can somewhat gauge how hard your heart is working. But have both tools. If you can afford a PM you can surely afford a cheap HR monitor.

gurk700

Also a note, no matter what people say, if you wanna train seriously, you NEED a PM.
Intervals with HR meter is a joke. You WILL get better the more hard rides you do but you WILL hit a wall at some point and you need data to train in specific areas of what you lack.
If you're a beginner, any kind of training will make you better. Don't let that lead you to believe PM is useless.

asgelle

OBoile

That's going a bit far IMO. I'm fairly certain all the pros from previous generations were training seriously despite the lack of PMs.

gurk700

Yes, but they were limited. Maybe I worded it wrong but I guarantee you anyone on earth will go further with a PM than their full potential without one. If past generations used a PM, they would've gone further too. All relative.
You simply can't gauge your effort accurately without one.

That said not eveyone cares either and that's absolutely fine. You can be a strong rider who never checks PM. If you're not looking into getting even better or competing, there's no need for one.

noodle soup

Where is @Doge when we need him?

OBoile

I agree with all of this.
I would say it's more about measuring output accurately. Effort is largely self judged.

I'd say you still don't need one... but, without one, you probably won't be as good as you could be.

OBoile

Lift weights! Here's the next TT world champ:

Truly the Mountain that Rides!