Heart rate monitor training. It’s a fascinating thing. You figure out your maximum heart rate (there are various tests—with the apparently obligatory medical warnings about maxing out your heart rate, and/or formulas: 220 — your age; 205.8 — 0.685 x your age).
Once you have your maximum heart rate (or some approximation thereof), you pick your training zone: 60-70% of your maximum heart rate for weight loss, 70-80% of your maximum heart rate for aerobic training, 80-90% of your maximum heart rate for anaerobic training. And you start.
The initial frustration is how quickly your heart rate soars well past the upper limits of your chosen zone. You were going for weight loss, let’s say (60-70% mhr), and you’re looking at a heart rate that’s up around 85% mhr, thinking to yourself with no small amount of irritation, “Why do I have to run so slow? I might as well be walking. I can do so much more. I can run so much faster.” But your heart rate stays high, and your pace gets slower and slower, and so it goes ….
Until the day you realize you can’t get your heart rate to where it needs to be without totally pushing your legs and your breathing beyond what you think they can do! And it’s reversed. You’re pushing yourself harder than you can believe, but your heart rate won’t get up to where it’s supposed to be! And so it goes … until it reverses itself again! The stronger system strengthens the weaker until what was weaker grows strong enough to strengthen what was stronger, and in playing systems off each other (muscular and aerobic against cardio-vascular), you strengthen each, and they make for a healthier you.
In like manner, some yoga poses have you twisting your hip one way (in) and the knee on the same side of your body the other way (out), and it is precisely the tension of the twisting that generates the stress that strengthens muscles and enhances balance.
Of course, too much tension will blow out a joint. Too much tension is destructive. But carefully setting the systems of a larger whole against each other—with the systems themselves submitting to the priority of the whole—understanding that no system of the whole is more important than the whole, well, that can be a very good thing indeed.
Now, why is that so hard for couples and families, individuals, congregations and Congress, denominations and the Church to grasp?