Some stationary bikes provide for both foot pedals and moving handle bars, so you can get a really good aerobic workout by working both your legs and arms. The Schwinn Airdyne Bike is one example of that type. Your can get a pretty good aerobic workout just pushing the handle bars without using the foot pedals, provided you can comfortable rest your feet on the foot rests. Some people with bad knees use the bike that way. Schwinn bikes or other similar types are often available in fitness centers, or in physical rehab centers, or you may be able to rent one for a few weeks. They cost about $500, and are worth it, but only after you have tried one and know it's right for you.

Catherine: I used to have a bike repair business. If the hose clamps don't work, you might try cutting a strip of metal from an aluminum can, loosening the clamp, slip the metal around the seat post, under the existing clamp, and tighten. OR, take your photo to a good bike shop and talk to a mechanic. They should have at least one solution. Good luck, Steve

I'll bet Moni could do it ;) My brother has gone to the spinning sessions and he's not a kid, but not recently I don't think. He goes in spurts where he's devoting all kinds of time to getting fit, but doesn't stay with it and is heavy again now. He's an all or nothing kind of guy, he doesn't ever do 'a little' of anything, so if he can't go to the gym and spend hours, he doesn't find a half hour to exercise in some other way. I figure some is better than none, have a stationary bike in my office and ride it most days, 6-8 'miles' - not as much of a workout as my doctor would recommend.

The NYT article brings up good points about the inaccuracy of max HR formulas, but HR can still be a good indicator of tracking intensity for a lot of people. It was scientifically tested but not meant to be the be all and end all like how it has been used. People like Seals have proposed other calculations than 220-age for max HR. At least with my undergraduates, when we test them on the treadmill with the metabolic measurement system they are often within 2-3 beats per minute of their age-predicted max. I had a maximal nuclear stress test earlier this year because I was having dizziness which luckily was not cardiac related, just vertigo. My age-predicted was 169 and I reached 171 at max--and I told the techs I was going for max, but I've always followed the formula. The only way to really know your max HR is to have a maximal test and measure it, but that's not something everyone can have done. You can also use perceived exertion aka Borg scales as a check. We recommend this a lot, especially if someone is using medications that may affect their HR like beta-blockers and/or if they have other chronic health problems. You can either use the original 6-20 scale or use the the modified 0 to 10 scale found in most health clubs. http://www.cdc.gov/physicalactivity/everyone/measuring/exertion.html http://my.clevelandclinic.org/services/heart/prevention/exercise/rpe-scale