In the morning I do 100 star jumps while the espresso is underway - gets the heart pumping and joy happening. Through the day, if working from home, I've found that doing 20 < 100 jumps an hour with the e-chimes feature dinging the hour means my back never gets sore from sitting at the computer. Instant gratification. Silent, painless and graceful aerobics. Best money spent in a long time.