iPhone erg app

[ErgCalc]

Hi all,

I hope this is not against any rules of spamming.

I just released an application for the iPhone that allows rowers and coaches to compute split times, overall times and distances. It also predicts possible erg times for other distances, based on 'Paul's Law' - you can find it at http://ergcalculator.com ($1.99) or in the App Store (search for ergcalc).

As a coach (and rower), I often find myself in need to answer the same kind of questions - 'What kind of pace should I maintain for this 6K-piece, my 2K is a 7:58?', etc.

I'd like to incorporate much more - the version I'm currently testing already has weight-adjustments built in ("X weighs 180 lbs, 7:30 2K; Y weighs 160 lbs; 7:40 2K - who would be a better fit for my eight?"), and does some more calculations on pieces - SPI / DPS. Logbook functionality is in the planning too.

I've originally written this for my own use, and I've been using it for a while now - people around me found it handy, so I decided to put it up on the app store.

Any feedback or suggestions are very welcome!

[ErgCalc]

The latest version has appeared in the app store. I added functionality to calculate Watts, Kcalories, DPS, SPI, and weight adjustments.

This information is typically available from the PM3 too, but sometimes I want to calculate it on historic pieces.

I use the weight adjustments to quickly look up how one result stacks up to another.

Next version: a Wolverine Plan L4 timer ("1:20 to go at SPM 18, then 2:00 at SPM 16") and storing workouts. Hopefully by the end of this week.

Download from itunes or see the website http://www.ergcalculator.com.

[philwhite7]

Just got the app and it works great - very convenient whether you row at home or at a gym. Easy to use, accurate and quick - exactly what I needed.

When's the Wolverine Plan addition coming and will I be able to upgrade to the updated app for free?

Phil

[nycbone]

I really like the app and have a few questions/suggestions:

A 'clear all' button for the pace/total time/distance calculator (main screen) would be helpful.

It seems that the Paul's law calculations are not corrected for weight. Is that correct?

It also seems that the kcal, stroke power etc. calculations on the details screen are not corrected for weight (I get the same estimates from my PM3 - not weight-corrected). Is that correct?

If so, having the weight correction for time/distance in an 8+ boat on the same page as the kcal, etc. calculations is a bit confusing. However, the explanation of the weight correction is quite clear.

It would be interesting to also include weight corrections for kcal, etc. as well. Concept2 has a weight correction coefficient calculator on its web site - perhaps something like that. Perhaps have all of the weight-corrected calculations on a separate screen.

My $0.02. Keep up the great work!

[ErgCalc]

Just got the app and it works great - very convenient whether you row at home or at a gym. Easy to use, accurate and quick - exactly what I needed.

When's the Wolverine Plan addition coming and will I be able to upgrade to the updated app for free?

Thanks for the feedback!

I am currently testing the WP addition with my team - I posted a screenshot in the Wolverine Plan thread, hoping to get some feedback before finalizing it. Here's the screenshot:




.. and here's the Wolverine Plan thread post: http://www.c2forum.com/viewtopic.php?t= ... &start=135

I hope to finalize it this weekend or early next week, and then push it to Apple. It takes a few days for an update to get posted.

Updates to an app you've bought on iTunes are always free!

[ErgCalc]

I really like the app and have a few questions/suggestions:

A 'clear all' button for the pace/total time/distance calculator (main screen) would be helpful.

It seems that the Paul's law calculations are not corrected for weight. Is that correct?

Thanks for the suggestions, really useful!

You are correct: Paul's law calculations are not corrected for weight. I use these to set target splits for longer/shorter pieces - and since the PM3 doesn't weight adjust, predicted splits don't weight adjust either.

Similarly for in the boat: my SpeedCoach doesn't know my weight, so doesn't adjust. So predictions shouldn't be adjusted either, I think.

It also seems that the kcal, stroke power etc. calculations on the details screen are not corrected for weight (I get the same estimates from my PM3 - not weight-corrected). Is that correct?


If so, having the weight correction for time/distance in an 8+ boat on the same page as the kcal, etc. calculations is a bit confusing. However, the explanation of the weight correction is quite clear.

It would be interesting to also include weight corrections for kcal, etc. as well. Concept2 has a weight correction coefficient calculator on its web site - perhaps something like that. Perhaps have all of the weight-corrected calculations on a separate screen.

True as well. The number given for watts (and it's per-stroke cousin SPI) is a measurement of the amount of power it requires to make the flywheel spin. The number is not dependent on the power source; it wouldn't change whether that power is generated by my 10-pound cat, a 100-pound coxswain or a 220 pound heavyweight Olympian.

The amount of calories required to generate that power is dependent on someone's weight; the current formula is the same that Concept2 uses:

This formula assumes a person of 175 pounds (80 kg) and a base rate of 300 cal/hour to move your body through the rowing motion at 30 strokes/minute.

I think it'd be a great idea to make the Kcal-reading dependent on weight, so I'll incorporate that in a future version!

My $0.02. Keep up the great work!

Thanks!

[nycbone]

Re: Paul's law, power and calories.

That all makes sense. It's clear that you've done your homework! If only I could keep up with Paul's law...

Looking forward to seeing the new update.

Dave

[philwhite7]

Ergcalc,

Thanks for the news. I checked out the WP thread and saw that nobody had really commented on the WP update to Ergcalc. It'd be nice if you could engage Mike C on v.2 of this update.

My humble input is:

The screenshot you showed looks like it will help with WP Level 4 workouts, which is perfect. Another nice feature would be the ability to input your 2K time and have the app give you WP Level 4 paces (for 16, 18, 20, 22, 24 and 26 spm). It's always a pain in the arse to get to the gym and realize you've forgotten the piece of paper with the L4 pace times on it.

In the meantime, please keep us posted on when the WP update will be available via iTunes. Ergcalc is a valuable training aid, and I appreciate your efforts to refine it.

Phil

[Nosmo]

If one does L4 work outs with slides and attached the iphone to the erg, then perhaps you could use the accelerometer in the iPhone to count strokes and or to give feed back if you one is a head or behind in the count.

You could also add a bar graph "metronome" similar to the ErgMonitor software to indicate stroke timing--you wouldn't need the accelerometer for this.

I think I would find counting strokes most useful. I think I always hit the number of strokes correctly but I do not have a way of verifying it (well I could use erg monitor but I don't because it is not convenient for me).
I've long ago learned what paces to use at each rates and I rarely get confused about where am I in the sequences any more. I do have a chart all the sequences and meters per sequence taped to my erg.

[philwhite7]

Good ideas Nosmo.

When I referenced "2K time" in my previous post I meant 500m split for 2k, just to clarify.

Nosmo - how do you log your L4 workouts in the C2 Logbook. I have a Model C with PM2, so a log card isn't an option. Should I add the whole session and the total distance (e.g 40 minutes, 10K ish) and then just write "WP L4" in the session notes, or break it down somehow?

Also, I'm currently doing L4s based on the 2K time I want to achieve rather than with my current 2k PB. It's going fine (for the first week!) and I'm hitting the target paces. Would you advise to just keep going?

Following Mike C's advise for four sessions per week, I'm doing:

Day 1. L1 or L2 (alternate each week)
Day 2. L4 - 40 mins
Day 3. L3
Day 4. L4 - 60 mins

[Nosmo]

Good ideas Nosmo.........

I'm going to copy this and respond in the New Wolverine Plan thread--Just to move that thread back up and because my response is not specific to the iPOhone erg app. See: http://www.c2forum.com/viewtopic.php?t= ... &start=148

[bloomp]

Phil -

I just log the distance/time and include a note as to what it was, e.g. L4 16/18/20 2' @ each. Then because I always post the work on the WTHYDT thread, I can just look up any piece in question and see my notes on it and breakdowns by split/sequence.

[ErgCalc]

I updated the app two weeks ago. The new version includes a Wolverine Level 4 timer, something that comes in very handy while coaching. If I have a group doing Level 4 workouts, I just program the iPhone, have someone be 'stroke' and have her call out rate changes.

The next version will have integration with the Concept2 online logs. It will work similar to the way the PM3 and PM4 connect with the LogCard utility: you maintain a log in the iPhone, but can sync it with the C2 log.

Also included in that version will be a better way to compute the amount of kCals burned. The newest addition computes kCals taking gender, age and weight into account (unlike the Concept2 PM*'s formula) - and it also approximates a daily energy expenditure.



allows you to d
I'm also thinking about calculating PARs for those that use that in determining diets. But I don't really know how many people actually would use that functionality, any suggestions?

Thanks again for your positive comments.

[Wannarow]

My Concept 2 rowing computer was stolen and I want to use my iphone and an app to replace it. Is there anything on the market that uses an accelerometer to track the distance on an erg? Any thoughts? Would the erg calculator do that?

[ErgCalc]

I have toyed with the idea - the signal that goes from the erg to the monitor is an auditory one; recording and graphing it out does give some information on wheel spin velocity. But the formulas that C2 uses to translate these into meaningful results are proprietary, and the best anyone can do is get numbers very close to them.

The iphone accelerometers could in principle detect stroke rate, but it'd require the iphone to be fixed to your body or to the seat. Not very practical.

The erg calculator gives none of these measurements, sorry.

Just out of interest: I've never heard of a PM to get stolen - what's the story?!