Training & Nutrition - Cycling, walking, activity equivalents.

Let me preface this by saying I know there is no simple comparison due to many variables.

However I want to know this as there is a 'fun competition' I am involved in where one enters/tracks steps walked, minutes cycled or step equivalents for 'vigorous activities'

The problem is that I cycle generally at 22-25mph (resulting in average speed of >20mph) - all level. The automated tool I enter the data in assumes if I enter minutes cycling that my cycling speed/effort is for 12mph. (or 100 steps/min) What is silly about this is the slower I go, the more steps I get!

The other option is to enter cycling as 'vigorous activity', but the conversion tables we are given only report cycling up to 15mph:

Walking at a normal pace = 100 steps/min
Bicycling (leisurely, 10-12 mph) = 100 steps/min
Bicycling (moderate, 12-14 mph) = 200 steps/min
Bicycling (vigorous, 14-16 mph) = 250 steps/min

If I look at this table: http://www.healthline.com/hlbook/dia-calculating-caloric-goals
It shows that the metabolic equivalent of cycling >20mph is 1.6x cycling at 14-16mph. So from this I calculate that if cycling at 14-16mph is 250 steps/min, then cycling at >20mph is equivalent 400 steps/min. (=250x1.6)

Does this logic hold up in a very general sense? Other folks are already complaining that I am racking up steps unfairly as I now have 2x the steps of anyone else. I want to show I am being fair. I think the reason I am 2x others in steps is because I cycle >250miles a week which is much more activity than anyone else. They think it is because I am cheating and not entering actual minutes cycled, but instead entering it as a very 'vigorous activity'

This is all for fun of course.

Al

In general, a pedometer isn't a good way to measure energy expenditure during cycling. Of course, you already knew that or you wouldn't try to be doing the calculations.

The proper calculations would require that you convert the energy expended during a walk of a certain interval to calories, then determine the number of bicycle miles, at your given speed, it would take to burn that same number of calories. Of course, there are a number of variables that would go into both sides of the equation so no reliable conversion factor could be derived, but if this is just for fun, then you should be able to do something.

This site: http://www.nopaperpress.com/site/1289793/page/821482 has a basic calorie calculator on it. According to it, if you weigh 150 pounds and walk at 3 MPH (the 100 steps/min speed), for an hour, you'll burn about 311 calories. Now, if you go to the Bicycle Speed and Power Calculator here http://www.kreuzotter.de/english/espeed.htm and plug in some basic numbers for a road bike (I used a height of 67", 150 pounds, hands on the drops roadster weighing 15 pounds, 68 degrees at elevation 1160 and a cadence of 90), I got a speed of 19.7 MPH. Reasonably close. If I then tell the thing that you ride that for 1 hour, it says that you expend 550 calories. This means that the cycling/walking ratio is 550/311, or roughly 1.77.

So, in the example above, your cycling is the equivalent of someone walking 177 steps/min. Of course, you should plug in your own numbers.

I'll also reiterate something I've said many times before, but which is still controversial. I don't believe that there is a really good reasonably priced way for the average person to accurately calculate the number of calories burned on a bike ride. The "rule of thumb (40 cal/mile)", the heart rate monitor, and the Speed and Power calculator all have different problems. They all start with some assumptions that may or may not be correct. For example, the Speed and Power calculator assumes that you're in shape, that you're riding a level grade, and that you're not stopping and starting again. Heart Rate Monitors rely on tables and/or calculations that may or may not be correct.

That's my opinion, anyway.

That's my opinion, anyway.
I appreciate it and agree about the 'controversial' calories thing.

Your method/calculations result in much lower 177 steps/hr for cycling at >20mph than even the extrapolated charts would suggest. Curious.

According to the tables given to us cycling at 14-16mph is already at 250steps/min

My 8.5mi flat commute walked at 20min/mi would theoretically burn 1086 kcal at my weight (185lbs)
The same commute run at 8min/mi is 11 (The conversion table indicates 200step/min for 8min/mi run)
The same commute cycled at 21mph with my stats would burn 420 kcal according to link you provided.

1086/420 = ~2.6 for the same distance covered

25min cycling at 20mph = 420kcal = 16.9 kcal/min
170min walking at 3mph = 1086kcal = 6.4 kcal/min
68min running at 8min/mi = 1189kcal = 17.5 kcal/min = 200 steps/min

So maybe it is more reasonable to use the cycling 14-16mph rate of 250steps/min per the table I was given, even though I cycle at >20mph.

Al

How about this?

Go out and get warmed up, and ride at your normal pace for 15 minutes or so. Stop and take your heart rate for 10 seconds. Remember that number.

Now, go out and walk, and see how many steps/minute you need to take to get into a similar zone.

I wish you luck. You see you are a pretty hard core aerobic athelete. Doing 250 miles per week at 20+ mph is pretty intense. You work at a level on a routine and daily basis that most people can not conceive of.

I think your modifications are probably reasonable. But a walker or any other low intensity exerciser just will not find what you are doing as believable. One thing you could do is take that fastest speed for which you have energy data like 17 mph. If you ride 51 miles, that is 3 hours at 17 mph so figure up your calories or energy based on a 3 hour exercise time even if you did it in less time. By the way, this will underestimate your true output because at lower speeds, one does not contend with the wind resistance. But given you levels of exercise, you can spot the group a fair bit and still end up way ahead of everyone else.