The problem with sitting for long periods of time, or remaining in any static position really, is that as muscles fatigue more stress is put on joints and bones. Having more muscle and strength helps significantly, but not all forms of exercise develops muscle and strength adaptations equally.
It would depend on the exercise. If you by "exercise" mean superflous human movement for the purpose of wasting excess energy, I would agree it doesn't do much to counter sitting the rest of the day, it's basically just a break from sitting.
If you instead mean methodical heavy barbell training for the purpose of invoking physiological adaptations in the form of increased muscle and strength, it would probably do a great deal to offset sitting for the rest of the day, especially coupled with the increased awareness and understanding of spinal positioning that comes with lifting weights.
Most of the time when people talk of "exercise", they mean the kind that don't do much for muscle and strength development (mainly the aerobic kind or light anaerobic work), but a lot of people actually do the kind that does.
It would depend on the exercise. If you by "exercise" mean superflous human movement for the purpose of wasting excess energy, I would agree it doesn't do much to counter sitting the rest of the day, it's basically just a break from sitting.
If you instead mean methodical heavy barbell training for the purpose of invoking physiological adaptations in the form of increased muscle and strength, it would probably do a great deal to offset sitting for the rest of the day, especially coupled with the increased awareness and understanding of spinal positioning that comes with lifting weights.
Most of the time when people talk of "exercise", they mean the kind that don't do much for muscle and strength development (mainly the aerobic kind or light anaerobic work), but a lot of people actually do the kind that does.