Harold74

I'm on a training program whereby I need to stay strictly within Zone 2. This is a piece of cake on my Wahoo Kickr where I have both heartrate and power data. That said, it's summer and I would also like to train outside.

Outside, 90% of my riding is on an awesome, multi use path around a reservoir right outside the door of my house. As awesome as the ride is, I struggle to stay in zone two based on my heartrate alone. It's a lot of acceleration and deceleration as opposed to a steady grind which, frankly, makes the ride fun. I don't yet have power on my outdoor bike but, as of now, I'm considering it.

Does power tracking make it easier to stay in zone two on outdoor rides? I consider heart rate to be the gold standard of Zone 2 determination but, at the same time, heart rate tends to be laggy in a way that power is not. Can anyone confirm or refute my assumption that it would be easier to train in Zone 2 with a power meter? The power meter will be a big investment but, if it gets me doing Zone 2 reliably outdoors, I'm in.

Eric F 

If you're riding on terrain where it's difficult to maintain a constant effort, staying in a specific training zone is going to be difficult, regardless of how you are monitoring your effort. That said, a power meter might be helpful in limiting the efforts that push your HR above your target zone. Learning how different effort levels feel in your body is an important piece of the puzzle, too. For me, on the road, I tend to pay attention to HR more than power.

Carbonfiberboy 

No. HR better, breathing even better than HR. Power in Z2 will vary by Z2 training volume, HR will vary less, breathing won't vary. Basically, it's the exertion level below the point where your deep breathing rate begins to increase.

Unfortunately it's actually more complicated than that. The way most zone calculators delineate Z2 is somewhat random. Here's a discussion of how to find your Z2 levels: Note that a power meter won't help unless you've been to the lab.
https://peterattiamd.com/how-to-find...lactate-meter/

One should also mention that there are two internationally used systems for numbering zones. In the US, most people use a 5-7 zone system where "Z2" is the zone in which the OP is interested. In Europe, many people use a 3 zone system, where the upper limit of Z1 is located at the upper limit of the US Z2.

Harold74

Yeah, the Attia stuff is what my current plan is based on really.

Breathing, sadly, isn't of much use to me. It's my nature to underestimate my level of effort so I really need something more objective.

I disagree that a power meter would not help. What I've done indoors is calibrated my zone two based on heartrate and breathing and then worked out wattage based programs that gets me to those targets consistently. That's been working wonderfully. My hypothesis is that I ought to be able to enforce wattage outdoors in real-time and use that as a way to achieve my target heart rates +/-. That, acknowledging that all manner of outdoor "stuff" will tend to affect my heartrate in ways not present in the indoor situation. Following my heartrate seems too see-saw-ish so far. I'm always high or low for a variety of reasons and often feel as though I'm reacting inappropriately because of the lag. I'm hoping that using power instead will have a flywheel effect of sorts so that I can ride a bit more smoothly.

Similar to what I do indoors, I'd like to ride based on power, check out the heartrate implications when I get home, and then adjust my power targets accordingly.

Eric F 

The challenge I found is that I can spike my power meter number for a brief time, but it will have little effect on my HR. The lag and slower reaction of my HR makes for an easier needle to control (for me). However, there's a learning curve to backing off your effort just a touch to inch it back into your target zone. Again, this is going to be more challenging on varying terrain. I'm lucky to have access to a 3mi un-interrupted loop with mild grade changes. Even then, sustained zone work is much easier on the trainer.

Carbonfiberboy 

Yes, power will help you to smooth things out, however its average will vary with training and training state. It does take a lot of practice to corral all three measurements and keep them in some relation to one another.

Using power outdoors drives me a bit nuts because of the large variations even on the "flat" which is never actually flat. I've found the most important thing is to keep one's cadence even, let power vary as it will within limits, while holding breathing even and HR also within certain limits. It takes a while for power levels to affect fat usage and lactate levels. Breathing rate however is quite closely related to metabolism as is HR.

Indoors is a completely different condition where holding power steady works perfectly.

terrymorse 

For maintaining a heart rate within zone 2, yes. A power meter responds quickly to a change in power, so it can guide you quickly to speed up or slow down as needed.

I use both a heart monitor and power meter, and I roughly know the power levels that keep me with zone 2 heart rate. If I look down and see power above that range, I know to back off a bit.

But I don't do strict "must stay in zone 2" rides, as I don't see the value of being that regimented. "All roads lead to Rome".

Harold74

Thank you, all, for your input. Data points...

Clearly, not having yet ridden outdoors with power, my impression of its awesomeness needs some tempering. Anybody wanna mail me their power pedals to demo for a week?!?

That speaks well to how I've been envisioning using a power meter. When I ride the route that I ride, all manner of "events" cause my heartrate to jump temporarily. When that happens, it can easily take a minute or more for my heart rate to come back down. Sometimes as long as five minutes. During that time, which feels like hours:

1) I'm flying a bit blind as to whether I'm expending the right amount of effort and;
2) Another "event" may well take place. Bunny hopping a dachshund, passing a group, or whatever.

On the other hand, I would think that I could correct power surges on timelines closer to five to ten seconds and then just trust that my heart rate will come back down to a level commensurate with the power based on historical performance.

Inugo San Millan's data backed theory is that, once you leave zone 2 for an appreciable stretch, it can take a long time to get back to it because you've triggered metabolic events which don't switch off easily. So once you leave zone two in the context of a 60-90 minute ride, that's the end of your zone 2. Having begun to drink from the fire hose of glycolytic energy, it takes some doing to convince your body to go back to gnawing away at the fat stores.

The stakes with this are abnormally high for me. I'm an unmedicated, lean type 2 diabetic which means, among other things, that I don't have many levers to pull with respect to keeping myself in remission. I'm banking on the strict zone 2 training -- to the tune of 6+ HRS / week -- to yield the mitochondrial improvements that I need rather desperately. In San Millan I trust... for now.

asgelle

You may want to check out the interview linked in the first post in the Coggan's Razor thread.

Harold74

Ah... I see. I am late to the party in discussing this. Thanks for the tip on the Coggan work.

terrymorse 

I wouldn’t put much confidence in that theory. Exercise physiologist Andy Coggan said there is no scientific evidence to support it.

GhostRider62

To stay within "zone 2", this is what I have found.

Lactate>Power>breathing>Hr

I like to amuse myself with guessing my power output by feel in my legs and surprisingly, I can guess pretty closely what my 3s Pwr is reading on the Garmin. Breathing also works for me. I cannot tell what my HR is and it lags for physiolofical reasons beyond what I want to write. My lactate levels do not correlate well with the 5 or 7 zone models and they vary tremendously by the type of training plan and level of fitness. The Maffetone HR method is about as good as any in terms of keeping you to that lower aerobic level for your metabolic training needs. It works for me especially if I keep the efforts down on hills. If you are good with math in your head, you can calculate your power while riding hills knowing the gradient, the speed, and your weight.

https://philmaffetone.com/180-formula/

MoAlpha

Unpopular opinion: Pay attention to power, HR, and perceived effort on the trainer and then use RPE once you are calibrated. As the coaches say, “if it feels hard, it is hard” and the real physiological stress induced by a given chunk of power x time varies from day to day according to your baseline state.

Jughed

Unmedicated T2 here as well, in remission as well.

I don't think Z2 is your only lever - I do ride at lower intensities most of the time, but I also incorporate blocks of high intensity training over the winter or to "tune up" in the summer. I also pick days to just let it rip, Z3/Z4 rides just for the sake of speed and blowing off some steam.

I pull all the levers from time to time, with no difference in BG's or A1C - in fact, the fitter I get from all training, the better the numbers.

As said above, maintaining tight Z2 power levels on the road is a crap shoot. Even on the "flat" bike path I frequent, 2-3' changes in elevation, up and down slight grade changes you may never even notice, can have big effects on power. Then you have hills, accelerations from stop signs or unintended accelerations... very difficult to use power for Z2.

Even Z4 efforts on my flat path are difficult to keep in range. I'm getting better at maintaining a 20+/-w window, but sometimes you will look down and you are 80w low on a downward grade that you can't even feel, followed by a 100w high on a slight rise.

RChung

I'm not a fan of strict Z2 but if you are, and if you consider HR to be the gold standard, then use HR. Under those circumstances, power will likely drive you nuts.

Plus, indoors you can get away with constantly monitoring HR and power but outdoors you should probably be paying more attention to traffic, dogs, and potholes rather than staring at your head unit to micro-manage power. Using power to "steer" HR is sort of like driving in reverse where you're using the front wheels to steer the rear of the car. You can do it but it either requires that you do it at slow speed or that you have had a lot of practice.

I think that RPE on an indoor trainer can be different enough to RPE outside that while they sort of transfer, they're not perfect substitutes.

MoAlpha

Yeah, that's a problem and HR can help solve it.

Carbonfiberboy 

Yes, it's just way easier to ride outside than in. Outside, I hardly notice my legs while riding at the same average power indoors my legs start to hurt much earlier. I think outdoors we get more power variation, meaning that we get little rests which make all the difference. So maybe on a 6 hour ride I have an average HR of 118. If I sat on my rollers for 6 hours at a steady 118 . . . well, impossible. I couldn't do it. And there are all those photos of Froome staring at his head unit. Don't do that. I have a riding buddy who rode into the back of a parked SUV and was injured. The SUV was fine.

GhostRider62

I can do a higher NP outdoors but a higher average power indoors (with a huge blower cooling me) although I don't like riding indoors at all. It is worse than cleaning the bike after two back to back rain days.

MoAlpha

I have theories too, some on the motor and some on the sensory side. However, I've never standardized the two power meters involved, so it's all silliness at this point.

PeteHski

I find power very useful for calibrating my efforts outside, especially on steady climbs and TT efforts. But staying strictly at Z2 power outdoors really requires a very flat route. My local routes simply do not allow it, regardless of what I measure. Technically I could probably do it by crawling up every climb and pushing more on the descents to keep power in range, but it just isn't fun riding like that and a very inefficient way to cover miles (if you get into the habit of riding like that).

So what I do for Z2 outdoor training rides is ride on RPE and keep an eye on my HR and Power on the steady parts of a climb or flat. Without a PM it is very easy to over-cook your power at the start of a ride, particularly on the climbs. I see this all the time with my riding buddies who don't have a power meter. They shoot off up the first climb we hit and ask why I'm holding back. Then I tell them what power we are putting out and they are surprised. For me that's the value of a PM for outdoor rides. It just calibrates your efforts during the course of a ride, from when you are fresh, through to being more fatigued at the end.

Hermes

With respect to perceived level of effort and difficulty...Trainer > track (fixed gear) > road. I use the road as the base case and derate workouts from there depending on training modality.

I like power levels and RPE as well as the conversation test for riding in z2. I look at HR but my HR can be lower after a harder previous day or vary for a number of reasons that have little to do with the training objective. If I use the San Millan conversation test then my HR will be higher and more like z3 as per Coggan.

Gold standard. Do the ride. My gold standard standard is make every pedal stroke count.

ZHVelo

I am curious as to how you think getting a power meter would change your ride on said undulating path. All it would do is show you that you keep popping out of and into zone 2. Something you already know now based on your HR. You need a route that allows for a constant effort.

ZHVelo

What is wrong with being slow up climbs? If you do a zone 2 ride you do a zone 2 ride.

Harold74

That question is the very reason for this thread: to enquire whether or not power management can be used as a proxy for heart rate management for the kind of riding that I'm doing as it can in more controlled situations. I'll put you down as a "no".

Since I last posted in this thread, I've figured out how to successfully hold my zone two heartrate constant on my variable route:

1) I hold my cadence between 65 BPM and 70 BPM rather than my usual 85 BPM - 95 BPM range.

2) I hold my pedal force to the level that I seem to naturally gravitate towards when optimizing pedal efficiency. Pushing comfortably but not mashing per se.

It's basically a version of this I think:

This has been working like I charm and I can do it quite well by feel so I probably won't get a power meter this year.

That said, a power meter might help me perfect my method even more if it could display pedal force instead of power. Is that possible? I would assume that force is the fundamental variable that power meters actually track so whether or not that is available is probably just a matter of how things are set up for display purposes.

Harold74

I listened to the Coggan podcast over the weekend. That was an interesting counter so some of San Millan's stuff. My thanks go out to everyone who pointed me in that direction. Hopefully they get around to ironing out their differences at some point and it's not one of those "science moves at the pace of funerals" kind of things.

I'm torn as to whether or not I'm happy to know about the Coggan stuff. Rationally, this is where my head's currently at:

1) There's a pretty good change that all roads do lead to Rome as you and Coggan say but;

2) The zone two road almost certainly leads to Rome.

Given how badly I want to get to Rome, it make logical sense for me to stick with Z2. So, while it's a relief to feel that I can probably be less strict about zone two, it's annoying to know that I could probably -- but not certainly -- ditch zone two altogether and just go back to to the hell for leather 20 minute all out efforts that I enjoy much more than Z2.