Forcing myself to exercise

Today i manage to resume my yoga lessons after stopping for like a few months.... hehe... more like half a year.

I fidgeted, hesitated and literally drag and force myself to the class because i think i have been sitting too much, inactivity too much for too long. Can start to feel neck ache, back ache and all kind of aches that signals lack of exercise. Do you ever need to force yourself to exercise ? Its so hard, and i keep giving myself excuse not to go. Its like both the angel and demon within me waging a war... and I am psychologically torned apart.

There is a swimming pool the place i live, but i'd always find excuse for myself for not taking a dip in the pool. The weather is too cold - might catch cold, the sun is too hot - might get sunburn, too many ppl in the pool...... not in the mood for swim ..... these are among the excuses i gave myself not swimming.

Why do humans have to exercise to stay healthy ? ....will there be a future technology to make human stay healthy without exercising ? For lazy people like me, that sounds like heaven.