Energy-based model explains how chronic stress transforms into disease over time

Does it mean exercising regularly does the same?

Exercise seems to stimulate the mechanisms it’s claiming stress depresses, so probably no.

But exercise does use lots of energy. Probably more than stress.

The body tends to use the same amount of energy regardless of what you do in a day. You can certainly over exercise which causes undue stress on the body. However other than an adaptive period at the start of regular exercise your body adapts to the increased caloric use from exercise by down regulating other processes to conserve energy. Typically an excess of calories is used by production of lipid fluid in adipose tissue and over expression of global inflammation. Once you begin exercising regularly the body generally stops using stored lipids for extra energy to compensate for the exercise and instead down regulates inefficient and generally harmful processes like random global inflammation.

As mentioned the Goldilocks zones are where you’re not forcing the body beyond what it can safely allocate to exercise in a day without causing stress in other processes. Generally though that Goldilocks zone is significantly greater than most people do in exercise in a week, but would typically fall in the zone of “moderate” exercise from a clinical point of view. This is effectively 3-6 times the expenditure of energy from rest for 150 minutes per week spread over a week for at least 10 minutes of moderately strenuous exercise at 70% heart rate per session. Most people in their 40’s or 50’s would typically find this fairly grueling, but that’s because of that homeostatic adaptation - the body resists changing its homeostasis and induces all sorts of negative experiences during the adaptation phase. Once you’ve adapted the opposite feelings present for the same reason - you begin to crave a routine of exercise because you body resists the adaptation to a more sedentary life.

N.b., This is why while exercise definitely helps lose weight, it’s primarily by managing inflammation and mood. This is why the only significant way you can lose weight over time is to reduce caloric intake materially under your homeostatic energy consumption.