22 May 2004 22:21:57
David Ranc
Force applied per stroke

Hello, this is a rather arid question. I hope it makes sense.

How do you know what force is applied to each stroke? It doesn't seem like
this is what the watts section of the computer give: I get higher values
when I apply less force but take the rate up.

Some people have told me about calculating the number of meters per stroke
but I am not sure this works!

The point is to compare similar pieces (45 min) done at different rates.

Thanks for the help.

D.R

H


23 May 2004 09:37:14
Ben Thomas
Re: Force applied per stroke

I assume what you want is the energy per stroke: this is how much energy you
give to the flywheel each stroke. Assuming your stroke length does not
change, this will be proportional to the force applied (how hard you are
pulling on the handle, but not taking into account how far you pull the
handle) for each stroke at any rate.

A watt is a measure of power, which is energy (in Joules) divided by time
(in seconds). Thus, to get the energy put in in one stroke, we need to know
how long a stroke lasts. This is given by:

Time for One Stroke = 60/Rating

Therefore, we have:

Energy Per Stroke = Watts * 60/Rating

"David Ranc" <dojr2nospam@nospam.cam.ac.uk > wrote in message
news:opr8e6yvlzwus5rf@nntp-serv.cam.ac.uk...
> Hello, this is a rather arid question. I hope it makes sense.
>
> How do you know what force is applied to each stroke? It doesn't seem like
> this is what the watts section of the computer give: I get higher values
> when I apply less force but take the rate up.
>
> Some people have told me about calculating the number of meters per stroke
> but I am not sure this works!
>
> The point is to compare similar pieces (45 min) done at different rates.
>
> Thanks for the help.
>
> D.R
>
> H




24 May 2004 03:11:52
Mark Campbell
Re: Force applied per stroke

"Ben Thomas" <bananathom@*SPAMLESS*btinternet.com > wrote in message news:<c8prca$gep$1@hercules.btinternet.com>...
> I assume what you want is the energy per stroke: this is how much energy you
> give to the flywheel each stroke. Assuming your stroke length does not
> change, this will be proportional to the force applied (how hard you are
> pulling on the handle, but not taking into account how far you pull the
> handle) for each stroke at any rate.
>
> A watt is a measure of power, which is energy (in Joules) divided by time
> (in seconds). Thus, to get the energy put in in one stroke, we need to know
> how long a stroke lasts. This is given by:
>
>Ben is right. You may be able to find a Rowperfect somewhere - if it
has an interface you will find that Energy/stroke is one of the
features, extremely useful when interpreted simutaneously with the
force curve. You can start to work out whether you perform best as a
"diesel" (low SR, high E/stroke) or "petrol" (lower E/stroke, higher
SR)

Regards, Mark


25 May 2004 00:15:50
David Ranc
Re: Force applied per stroke

On 24 May 2004 03:11:52 -0700, Mark Campbell <info@rowperfect.com.au >
wrote:

>> Ben is right. You may be able to find a Rowperfect somewhere - if it
> has an interface you will find that Energy/stroke is one of the
> features, extremely useful when interpreted simutaneously with the
> force curve. You can start to work out whether you perform best as a
> "diesel" (low SR, high E/stroke) or "petrol" (lower E/stroke, higher
> SR)

I know I perform best as a Diesel, unfortunately. I am just trying to see
whether I didn't work harder when I was rating 16 rather than 18. I need to
increase the output I can give on one stroke though and I was told that for
that I should do long ergs at a low rating. It does not make sense as I
always thought this was a way to build endurance... How wrong am I.

If I understand the idea behind the watt, if I multiply Watts by the number
of minutes, then I get the number of Joules used in the training session?
Don't I?

D.R


25 May 2004 09:38:53
Neil Wallace
Re: Force applied per stroke

David Ranc wrote:
> I know I perform best as a Diesel, unfortunately. I am just trying to
> see whether I didn't work harder when I was rating 16 rather than 18.
> I need to increase the output I can give on one stroke though and I
> was told that for that I should do long ergs at a low rating. It does
> not make sense as I always thought this was a way to build
> endurance... How wrong am I.
>

My understanding, for any given power output, the lower the stroke rate, the
more the exercise is tending towards strength building.
Long ergs at low rates have been a discussed here before. Some doubt their
effectiveness other than for those who train for 5 hours/day. Club rowers
with limited time are, IMHO better to go harder at it, for shorter periods.

> If I understand the idea behind the watt, if I multiply Watts by the
> number of minutes, then I get the number of Joules used in the
> training session? Don't I?

Nearly, try joules = watts x time (in seconds)





25 May 2004 18:43:28
Mark Campbell
Re: Force applied per stroke

David Ranc <dojr2nospam@nospam.cam.ac.uk > wrote in message news:<opr8i1koxpwus5rf@nntp-serv.cam.ac.uk>...
>
> I know I perform best as a Diesel, unfortunately. I am just trying to see
> whether I didn't work harder when I was rating 16 rather than 18. I need to
> increase the output I can give on one stroke though and I was told that for
> that I should do long ergs at a low rating. It does not make sense as I
> always thought this was a way to build endurance... How wrong am I.

No, not at all. I think a combination of the two is the answer. My
current theory on off-water training, though it has lasted for a few
years now, is to do a combination of low rate/high pressure and power
strokes aiming for well over my average E/stroke when racing. The
power strokes on the RP at @R26, using the small cog and maybe disc 4
or 5, depending how strong I am feeling. The low rate pieces around
30-60 minutes, two or three times /week, power strokes once or twice
/week. I could give you the exact figures I aim for, but then I'd have
to kill you...:-).

Regards, Mark


26 May 2004 08:04:02
PaulS
Re: Force applied per stroke

info@rowperfect.com.au (Mark Campbell) wrote in message news:<56543a0a.0405251743.29933270@posting.google.com >...
> David Ranc <dojr2nospam@nospam.cam.ac.uk> wrote in message news:<opr8i1koxpwus5rf@nntp-serv.cam.ac.uk>...
> >
> > I know I perform best as a Diesel, unfortunately. I am just trying to see
> > whether I didn't work harder when I was rating 16 rather than 18. I need to
> > increase the output I can give on one stroke though and I was told that for
> > that I should do long ergs at a low rating. It does not make sense as I
> > always thought this was a way to build endurance... How wrong am I.
>
> No, not at all. I think a combination of the two is the answer. My
> current theory on off-water training, though it has lasted for a few
> years now, is to do a combination of low rate/high pressure and power
> strokes aiming for well over my average E/stroke when racing. The
> power strokes on the RP at @R26, using the small cog and maybe disc 4
> or 5, depending how strong I am feeling. The low rate pieces around
> 30-60 minutes, two or three times /week, power strokes once or twice
> /week. I could give you the exact figures I aim for, but then I'd have
> to kill you...:-).
>
> Regards, Mark

Just supply a SES or STR file, I'll take the risk of having that information.

- Paul Smith


29 May 2004 17:28:43
David Ranc
Re: Force applied per stroke



On 25 May 2004 18:43:28 -0700, Mark Campbell <info@rowperfect.com.au >
wrote:

> No, not at all. I think a combination of the two is the answer. My
> current theory on off-water training, though it has lasted for a few
> years now, is to do a combination of low rate/high pressure and power
> strokes aiming for well over my average E/stroke when racing. The
> power strokes on the RP at @R26, using the small cog and maybe disc 4
> or 5, depending how strong I am feeling. The low rate pieces around
> 30-60 minutes, two or three times /week, power strokes once or twice
> /week. I could give you the exact figures I aim for, but then I'd have
> to kill you...:-).

Very interesting. What do you mean by "average E/stroke?"?
How long do you go for your power strokes?

D.R


31 May 2004 11:28:47
Neil Wallace
Re: Force applied per stroke

David Ranc wrote:
> On 25 May 2004 18:43:28 -0700, Mark Campbell <info@rowperfect.com.au>
> wrote:
>
>> No, not at all. I think a combination of the two is the answer. My
>> current theory on off-water training, though it has lasted for a few
>> years now, is to do a combination of low rate/high pressure and power
>> strokes aiming for well over my average E/stroke when racing. The
>> power strokes on the RP at @R26, using the small cog and maybe disc 4
>> or 5, depending how strong I am feeling. The low rate pieces around
>> 30-60 minutes, two or three times /week, power strokes once or twice
>> /week. I could give you the exact figures I aim for, but then I'd
>> have to kill you...:-).
>
> Very interesting. What do you mean by "average E/stroke?"?
> How long do you go for your power strokes?
>
> D.R


I suspect Mark is a lot stronger than I (a 34year old club rower), but I do
similar workouts (also on a rowperfect) 30mins SR 18, 250W.
Stroke energy BTW is simply an integration of force x distance, it needs to
be in excess of 800J.

This seems to tie in with Mark's observation that the e/stroke is above the
race situation.
For purposes of discussion, my figures in a 2k piece would be SE approx
640J, SR approx 31, Power 330W.

I wonder what the group thinks of this sort of workout for building strength
as opposed to weight training??