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There's a very direct relationship between the rotational speed (RPMs) of a bicycle wheel and the ground speed (MPH) of the bicycle. The only quantity that can vary from bike to bike that we must pay attention to is the diameter of the wheel(s). The larger the wheel, the more distance you cover per revolution... Anyway, we need to do a little math. Sorry, but that's reality. So, there are three quantities (variables) that we're interested in. Let's give them names: D = the diameter (distance from edge to edge through the center) of the wheel, in INCHES M = the ground speed in miles per hour (MPH) R = rotational speed (revolutions per minute or RPMs) of the bike wheel. You can calculate M using the formula: M = 0.003*D*R (read: 0.003 times D times R) or You can calculate R using the formula: R = 333*M/D (read: 333 times M divided by D) Example: my stationary bike says I'm going 10 MPH (M). As I said earlier, the diameter, D, of my bike wheel is 20 inches. Using the second formula: R = 333*M/D = 333*10/20 = 166.5 RPM, almost 3 revolutions of your bike wheel each second! Though your feet may not be going quite that fast, it'll seem like you're moving pretty fast. OK... I can hear it coming: "but when I ride a real bike, I can go 20 MPH without having my legs fall off from pumping so fast." That's right. That's what the gears do: when we change to a higher gear, we need fewer turns of the pedals to make the wheels go around. Notice that the formulas above pertain only to the front wheel: its rotational speed and the distance covered (as if it were on the ground, like a real bike). How fast your feet move also depends on the gearing. BTW - you'll notice that the notion of "resistance" does not appear in the above discussion. Resistance changes the amount of effort you must supply to attain or maintain a particular speed. So, for example, one must supply much more effort to pedal a bike up a hill as compared to pedaling on flat ground: the hill provides "resistance". Without changing the gears, you still have to move your feet the same if you want to maintain the same speed on the hill as you had on he flat. My apologies if the above appears simplistic. In my experience as a math teacher, it became clear that many lessons learned in high school days are easily forgotten. Roger Seymour -----Original Message----- From: Mary Ann Ryan Sent: Sunday, September 01, 2013 9:09 AM To: [log in to unmask] Subject: Re: Cleveland Clinic study This was written by Ray. -------- Mary Ann ----- Original Message ----- From: "john emrys" <[log in to unmask]> To: <[log in to unmask]> Sent: Saturday, August 31, 2013 7:42 AM Subject: Re: Cleveland Clinic study > Hey Mary Ann > > Have you tried getting in touch with the manufacturer of the cycle? > > > ~ J. > > > On 2013-08-30, at 1:23 PM, Rayilyn Brown wrote: > > I iam still trying to find out how many miles per hour I must cycle to > reach 80 rpms. does anyone know? I'm back to 10 mph now > > -----Original Message----- From: Mary Ann Ryan > Sent: Thursday, August 29, 2013 11:57 AM > To: [log in to unmask] > Subject: Cleveland Clinic study > > I visited my cousin, Barb, in Cleveland over the past two days. Barb had > been diagnosed with PD some time ago and hadn't been doing well. Her > gross motor function, particularly on her left side, had been compromised > to the point where she was having some difficulty walking. When I saw her > on Tuesday I was shocked. She looked almost entirely asymptomatic. I > knew she had been enrolled in a study at the Cleveland Clinic which > involved tandem cycling and that she was feeling much better. However, > the improvement I saw was stunning. She wrote this little over-view which > she said I could share - so here it is. > --------- > Mary Ann (CG Jamie 68/28 with PD, died 11/20/07) > I had a great discussion with the researcher with whom I work at the > Cleveland Clinic research facility. She explained that the premise of Dr. > Albert’s study is not only to regain function for those of us with PD, but > they see some preliminary results that point to the fact that the cycling > slows or even stops disease progression in some patients like me with > milder symptoms. Others within my group have a harder time maintaining > the speed required as they exercise less due to more serious symptoms (On > days I do not cycle I usually take a fairly aggressive water aerobics > class, so I came to the study with good stamina.). > > > > There is some evidence that the cycling can be as effective as medication > in addressing symptoms and can possibly regenerate some of the damaged > nerves. The trial includes stroke patients as well. While I understand > that: > > · My understanding is limited, given my non-medical background. > > · There are many more tests to run and data to collect, including > many of us undergoing per and post training MRIs to evaluate changes in > the brain due to the cycling. > > > > > She advised against firms that often advertise to PD patients as their > stationary cycles promote passive exercise. The trick of the trial in > which I am involved is to get me to the 90-92 rpm range on my own power, > with some machine assist (or a fellow tandem rider), while staying within > my heart range (117-130). When I complete the study and evaluation, they > will give me an exercise prescription that I will share with you so you > can tell your PD friends. > > > > Exciting stuff!!! > > > > > > Barbara > > > > 216-554-9100 > > > > > > > > > > > > > > > > Barb Belovich > > > > 216 554 9100 cell > > ---------------------------------------------------------------------- > To sign-off Parkinsn send a message to: > mailto:[log in to unmask] > In the body of the message put: signoff parkinsn > ---------------------------------------------------------------------- > To sign-off Parkinsn send a message to: > mailto:[log in to unmask] > In the body of the message put: signoff parkinsn > > ---------------------------------------------------------------------- > To sign-off Parkinsn send a message to: > mailto:[log in to unmask] > In the body of the message put: signoff parkinsn ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn