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gottoshopalot
03-28-2010, 10:54 AM
When my club recently purchased Keiser bikes a few months ago I became interested in learning about power training. All the resources I could come up with offered very complex explainations that totally confused me. Finally, I found the answer that I wanted to share with instructors that are in this same position. I just downloaded and read "The Power Training System for Indoor Cycling" by Pedal On member Gene Nacey and I had my "AHA moment" - it made everything crystal clear. I am ready to begin on the journey of Power Training and I can't wait!!!!

SpinBob
03-28-2010, 11:11 AM
Cathy,

I took the CycleOps Power certification and there is a lot of good information about training with power in that program, but of course there's a fee attached. To me the key for many people will be that generating one watt of power burns one calorie, so generating 3500 watts on a weekly, or biweekly, basis burns 3500 calories, which burns one pound of body fat. Obviously calorie intake needs to be constant to lose weight, but I think it gives most people the kind of feedback they are looking for.

zoepup
03-29-2010, 07:45 AM
Maybe this is too much to ask, but how does a power meter actually measure that you used one watt of energy? I understand how my Polar HR determines I burned a calorie but am befuddled by the power meter thing. I would love one on my road bike, but they are a bit pricey.

elsaltamontes
03-29-2010, 10:21 AM
It doesn't. Calorie consumption is "estimated" from wattage. The estimation comes from numerous lab tests in what is called a bomb calorimeter, which measures the amount of heat from a given effort(watts). Calories(kcals) is a unit of heat. I think the metabolic carts like new leaf could also accurately predict calorie production as well but I am not familar with that.

As far as a simple power definition...Power equals effort. It tells you exactly how much effort you are using every second. It is not percieved, guessed at or by feel. It is completely specific to each individual.

Physics definition... force * distance / time. force: how hard you push the pedals, distance: how far you push the pedals(constant based on crank length), and time: cadence.

Power defines everything you do on a bike into one all inclusive "effort" number(s).

Get a power meter for your bike...it will change your life!

zoepup
03-29-2010, 10:26 AM
It doesn't. Calorie consumption is "estimated" from wattage. The estimation comes from numerous lab tests in what is called a bomb calorimeter, which measures the amount of heat from a given effort(watts). Calories(kcals) is a unit of heat. I think the metabolic carts like new leaf could also accurately predict calorie production as well but I am not familar with that.

As far as a simple power definition...Power equals effort. It tells you exactly how much effort you are using every second. It is not percieved, guessed at or by feel. It is completely specific to each individual.

Physics definition... force * distance / time. force: how hard you push the pedals, distance: how far you push the pedals(constant based on crank length), and time: cadence.

Power defines everything you do on a bike into one all inclusive "effort" number(s).

Get a power meter for your bike...it will change your life!

Thanks! that puts it in simpler terms. I have a Garmin 705. What type of PM would work with that and is REASONABLY priced?

gottoshopalot
03-29-2010, 12:44 PM
Cathy,

I took the CycleOps Power certification and there is a lot of good information about training with power in that program, but of course there's a fee attached. To me the key for many people will be that generating one watt of power burns one calorie, so generating 3500 watts on a weekly, or biweekly, basis burns 3500 calories, which burns one pound of body fat. Obviously calorie intake needs to be constant to lose weight, but I think it gives most people the kind of feedback they are looking for.
Obviously nothing can take the place of a hands on training but for this book was a small investment and gave me some simple, uncomplicated answers I couldn't find anywhere else.

Our club got the Keiser bikes and I had no idea how to use a power meter. We didn't get any formal training so this book was a nice introduction. As far as Cycleops, I haven't been able to find any open trainings on the Saris webiste.

Bob, how is your fund raising coming along?
Cathy

SpinBob
03-29-2010, 01:49 PM
It doesn't. Calorie consumption is "estimated" from wattage. The estimation comes from numerous lab tests in what is called a bomb calorimeter, which measures the amount of heat from a given effort(watts). Calories(kcals) is a unit of heat. I think the metabolic carts like new leaf could also accurately predict calorie production as well but I am not familar with that.

As far as a simple power definition...Power equals effort. It tells you exactly how much effort you are using every second. It is not percieved, guessed at or by feel. It is completely specific to each individual.

Physics definition... force * distance / time. force: how hard you push the pedals, distance: how far you push the pedals(constant based on crank length), and time: cadence.

Power defines everything you do on a bike into one all inclusive "effort" number(s).

Get a power meter for your bike...it will change your life!Thanks for making what I said simpler. :)


Thanks! that puts it in simpler terms. I have a Garmin 705. What type of PM would work with that and is REASONABLY priced? Many manufacturers are in the process of switching from wired to wireless, so there may be some deals out there, but I don't think anyone considers the price of even an entry level power meter as reasonable.

SpinBob
03-29-2010, 01:52 PM
Obviously nothing can take the place of a hands on training but for this book was a small investment and gave me some simple, uncomplicated answers I couldn't find anywhere else.

Our club got the Keiser bikes and I had no idea how to use a power meter. We didn't get any formal training so this book was a nice introduction. As far as Cycleops, I haven't been able to find any open trainings on the Saris webiste.

Bob, how is your fund raising coming along?
Cathy
Cathy,
I'm at over 90% of my goal of $1,500, but I may raise my goal to $2,000 or $2,500 depending on how positive I feel. I'd love to have you donate.

Here's another guide for training with power. Remember the Keiser bikes only estimate power, they don't actual measure it.

http://www.midweekclub.ca/powerFAQ.htm

gottoshopalot
03-29-2010, 02:20 PM
Cathy,
I'm at over 90% of my goal of $1,500, but I may raise my goal to $2,000 or $2,500 depending on how positive I feel. I'd love to have you donate.

Here's another guide for training with power. Remember the Keiser bikes only estimate power, they don't actual measure it.

http://www.midweekclub.ca/powerFAQ.htm

You got it Bob. I think you have a link on your FACEBOOK page. Good Luck!!!!:)

Lisa
03-29-2010, 03:51 PM
We have the new Schwin bikes with the powe meters. Members are very curious as to how it can calculate thier Kcals used. They think it is not accurate if there is no way to input weight, gender, height, etc.

CycleGuy
03-29-2010, 10:00 PM
We have the new Schwin bikes with the powe meters. Members are very curious as to how it can calculate thier Kcals used. They think it is not accurate if there is no way to input weight, gender, height, etc.

Simplified (I hope) response:

Power is a function of force and velocity. Weight, gender, height, eye colour, etc. has no bearing in it. The same force applied at the same weight will result in the same power.

Think of a weight room in a fitness facility. The power needed to lift a 10kg bar 1 metre in 1 second is identical regardless of who is lifting it. A 50kg (110lb) female or a 100kg (220lb) male, the same amount of power is required. The effort experienced may be different because one has more muscle to perform the lifting.

The Saris website has information that essentially says that what most people refer to as calories (for weight loss) equates to a watt of power on the bike. Produce 100 watts (as per the power meter on the bike) over some period of time and you have burned 100 calories. This is 100 calories in addition to what you would have burned if you had done nothing but sit on the bike and stare at the instructor for the same period of time.

Lisa
03-30-2010, 12:01 PM
Thanks so much for the reply. I get it now :). I think what they are focusing on is their total calories at the end of the ride and the average watts. After completing the ride they can look at their averages. I'll show them how the average wattage corresponds to total kcals and also distance travelled.

Todd S
03-30-2010, 01:29 PM
The Saris website has information that essentially says that what most people refer to as calories (for weight loss) equates to a watt of power on the bike. Produce 100 watts (as per the power meter on the bike) over some period of time and you have burned 100 calories. This is 100 calories in addition to what you would have burned if you had done nothing but sit on the bike and stare at the instructor for the same period of time.

1 Calorie (dietary) is equal to a little over 4 kilojoules (not watts). Since we're all pretty close to being about 23% efficient at turning metabolic energy into mechanical energy on the bike, the number of kilojoules you see on your meter at the end of your ride will be pretty close to the number of Calories that you've burned.

Paul S.
03-30-2010, 07:27 PM
We have the new Schwin bikes with the powe meters. Members are very curious as to how it can calculate thier Kcals used. They think it is not accurate if there is no way to input weight, gender, height, etc.
They're probably thinking about the cardio machines that estimate power by using the speed, incline, and/or resistance of the machine in conjunction with that user-specific data, or HR monitors that do it with the HR measurement in conjunction with that data. The power meter works on a different principle, directly measuring the power, so the user-specific data is irrelevant.

We had an similar, extensive discussion recently: http://www.pedal-on.com/showthread.php?t=8698 (power discussion begins near the bottom of the first page through the second). It is important to remember the distinction between power (measured in watts or Calories per hour) and energy, which is power times time (meassured in watt-hours, kilojoules or Calories), as well as the difference between the metabolic energy expended and, considering that 23% efficiency, the lesser amount transferred to the bike.