Are my easy runs “too easy” (Heart Rate Zones)

Question

Are my easy runs “too easy”? (Heart Rate Zones)

My wife bought me an Apple Watch earlier this week, and I’ve been experimenting with using the heart rate zones it measures during my runs.

The majority of my runs are “easy runs” at a slow pace (or long slow runs at a slow pace). I’ve always made an effort to keep my easy runs real easy, at a sort of pace that I feel I can maintain more or less indefinitely. Also, I’m obese, so this is quite a slow pace (~13:30; in truth, it looks more like fast shuffling than running).

Anyway, what I’ve noticed is that when I run at my usual easy pace (based on perceived effort), I’m in Zone 1 the majority of the time, and will perhaps dip into Zone 2 towards the end of the run. For example, this morning I went on an 8.25 mile long run. The pace (avg 13:40) felt easy, but that I was running and not walking. My Zone 2 begins at 136bpm, and during the run I was 128-132bpm for the first 90% of the run, and only broke into Zone 2 for the last ten or so minutes.

I’ve read that in order to improve my aerobic base and burn fat I really should be doing these runs in Zone 2. Now, this isn’t a problem in the sense that if I speed up a little then I can get into Zone 2 and with some effort stay there without drifting into Zone 3 too quickly. Also, I know that the heart rate zones my Apple Watch is producing are likely far from perfect, and I’m certainly not going to completely ignore how my body feels in order to stick to what my watch says my heart rate zone is.

I guess what I’d like to know is, am I doing these runs too slowly? Based on my times in a recent half marathon and a few recent 5ks, which I plugged into a few online calculators, my easy pace is more or less where it should be. But at the same time, this seems to put me in Zone 1 and not Zone 2.

Answer 1

Zones are mostly meaningless and you shouldn't pay any attention to them.

The single most useful metric of how beneficial a run is likely to be is the distance of that run. A 6 mile run at a 7.5min/mi pace would be considered a similarly effective bout of exercise as one at a 10min/mi pace, it's just that the former only takes 45 minutes to complete, while the latter takes an hour. There's unlikely to be any difference in effect on bodyweight between the two.

Now, if you're finding that you don't have enough time to complete the runs that you want to do, or if you'd like to be able to run faster either to do better in organised runs or just to feel good about improving your pace, then attempting some (not necessarily all) runs at a faster pace would be beneficial. But it's not necessary. And if you're obese and weight loss is a major goal, then the most important thing will be the distance you're managing to run each week, with the optimal pace just being whatever pace allows you to get that done.