Trying to understand calorie burned

[salty]

Hi,

New rower here. I've got a lifetime total of around 16 hours on the machine, so yeah, quite new. I've spent a lot of this first time looking at videos and practicing the stroke, so I hope it's at least decent now. I did actually see an improvement in my times, which I think is from better form and not because I've gotten more fit.

Now then, what I'm trying to understand are calories burned as that's one of the main reasons for rowing. Having done a hard 30 minutes row, logbook shows 339 calories burned. It goes through logbook to Strava, which shows my average HR for this session as 153 and relative effort as 56.

Those numbers on their own doesn't mean anything to me, so I've also tried walking to have something to compare to. (Can't run.) For simply walking at a slow 10min/km pace for 30 minutes, Strava shows 220 calories burned, which I thought was surprisingly high compared to the effort. Can this be trusted, does it seem about right?
To check what it would take to match 30 minutes rowing I did another easy walk for 45 minutes, and that got me 334 calories burned with average HR of 120 and relative effort of 11.

The relative effort number from Strava really seems to match the effort I put in, as rowing was extremely hard, I was dripping with sweat and so on, but I only got a little warm from walking. How can it be then, or can it really be that those two efforts burn about the same amount of calories? It seems so counterintuitive to me, given how hard I was working for one, and how trivial the other was.

If this is about right then it seems I can burn more calories by simply walking a little everyday, as that is something I actually can do every day. After rowing I need a day, if not more to recover. Am I missing something here, or what is going on?

[Citroen]

The PM3/PM4/PM5 has the worst possible calorie counter. If you are male, weigh 80Kg, are 25% efficient at turning calories into work and burn 300kCal just by sitting on the ergo seat and doing nothing then you may have a chance of getting an accurate result. The only truth with the PM3/PM4/PM5 is that the results are consistent and repeatable.

Since there is nobody on earth who meets those criteria then you should use any other method to count calories.

Things that ask for your height, weight, BMI, etc. before doing their wonky maths are usually closer to the truth (within the bounds that there's not enough real science here).

Join in with the discussion in: viewtopic.php?f=9&t=190155 and you may learn the best of the worst ways of counting these things.

[Dangerscouse]

I have no idea how many calories you will be burning, or anyone else for that matter, as perfectly summed up by Citroen, there is no point looking at the calories on the monitor other than trying to use it as something similar to distance or time spent rowing.

I can guarantee you will be burning a lot of calories though if you're using it correctly and for long enough. Remember to go slowish and longer and don't think that thrashing yourself is the best option.

You should be able to have small sentences of conversation, and sing a verse or two of a song if you want a very rough guide for the best fat burning pace

[Allan Olesen]

First of all:
You can burn a lot of calories by walking every day. Andy you will actually also build a lot of fitness in the process. I know, because I did that two years ago.

However, there is one thing you should know about calorie information from recorded exercises:
These calories usually include the resting calories, which you would have burned anyway if just sitting on the couch. So the "net calories", aka "active calories" from an activity are lower than the indicated number.

You can easily test if this happens to you. Sit on the couch for an hour while recording an indoor run. If that run has a significant amount of calories (0.8-1 kcal per kg of body weight), it is because the recording contains resting calories.

For a hard exercise this doesn't mean much. If you burn 1000 kcal in an hour of hard work, most of those are actually active calories.

But for easy exercises like walking, this will lead to a huge error, and you will have to correct for it by manually subtracting your resting calories.

[Alan_Schenk]

153 average heart rate sounds quite high to me. As others have stated, the fat burning zone (on the assumption that such a thing exists) only requires you to be exercising at a level where you can still speak etc. Also, as the PM5 does not take into account height, weight, BMI stats etc, you will find that Concept2 do offer an adjusted calories page on their website for you to put your workout in, and it will calculate for you what it considers to be a more accurate amount of calories burned <https://www.concept2.com/indoor-rowers/ ... calculator>, as it will use your body weight in the equation. Anyone heavier than 75kg is going to have a higher calories burned figure than the monitor provides.

Also remember that rowing provides more benefits than just burning calories, so you may want to consider that as well. I myself have lost 29kg since January, which also included rowing (8000m 6 days a week, average HR around 125, drag factor 120). How much the rowing had an impact I can't say, no way of really knowing, but I certainly feel as though it is helping with tightening of muscles and using muscle groups that walking would not, even if I could walk every-day in the current 45+ degree weather we are having where I live.

At the end of the day, consistency is the key and doing something you enjoy is more likely to be maintained and therefore prove beneficial in the long-term. If that is not rowing and you prefer walking, then you have your answer.

[salty]

Thanks for all the replies! Lots of new and interesting information here! I definitely wasn't aware of the resting calories being included, for sure that skews the picture a bit for the easy walking sessions.

Rowing is what I want to do and get better at, so I'll see about slowing down. It's just this feeling, it feels like I have to go hard for it to have an effect. But yeah, I'll do some longer and slower sessions and see how that goes. There gotta be a sweep spot there somewhere, where it's possible to do everyday without getting too exhausted.

Thanks again!

[Dangerscouse]

Rowing is what I want to do and get better at, so I'll see about slowing down. It's just this feeling, it feels like I have to go hard for it to have an effect. But yeah, I'll do some longer and slower sessions and see how that goes. There gotta be a sweep spot there somewhere, where it's possible to do everyday without getting too exhausted.

Thanks again!

Very easy mistake to make, 'harder has to be better'. Over the years I have tried all sorts of strategies, and I can say I have found significant weight loss , and PBs, have both come from mainly doing long and slow distances, along with occasional short and sharp sessions.

Going hard all of the time just left me drained, and stagnated my progress. It's just your ego talking when you decide to do it, as there's nothing to boast about when you go slow.

[mict450]

At the end of the day, I think monitoring caloric output is an inefficient way to weight loss. Academically interesting, but of limited use in application, IMO. Unless one is a full-time professional athlete, the calories one burns during a workout is miniscule compared to one's total daily output.

Better to strictly monitor intake, by controlling portion size & food choices, if one wants to lose fat. This, I think, will give one the most bang for one's buck. If you don't eat it, you won't have to worry about burning it off. Consider whatever physical activity one does as the "cherry on the top." And all that extra "work" is further incentive not to "mess up" when sitting at the kitchen table.

[hjs]

Thanks for all the replies! Lots of new and interesting information here! I definitely wasn't aware of the resting calories being included, for sure that skews the picture a bit for the easy walking sessions.

Rowing is what I want to do and get better at, so I'll see about slowing down. It's just this feeling, it feels like I have to go hard for it to have an effect. But yeah, I'll do some longer and slower sessions and see how that goes. There gotta be a sweep spot there somewhere, where it's possible to do everyday without getting too exhausted.

Thanks again!

You should go hard, but not always, if you go hard “always” you end up never going really hard. Hard on the erg can be really hard if you ho at max. If you can go “hard” daily your sessions are not hard...

Re cal. That indeed gives a false picture, it would be better to only give the extra cal you burn, to tell you what your effort is worth.

[iain]

As well as the above, you need to think what else is happening to your body. Walking every day will help, but you culd still be losing muscle. I had several years off rowing, but walked an hour a day fairly briskly. My weight increased about 6%. At the end I restarted rowing and lost about 10% of my original weight, I had lost at least 4% of my original weight in muscle and replaced it with fat so things were much worse than I thought! Rowing helps to stimulate most of the larger muscle groups. If you do some harder rows then this can reduce or even reverse the muscle loss. The regained muscle will take much more energy to grow. You will also add some extra blood, caplliaries etc. that will further increase your lean mass as it is not the weight that matters but excess fat over the lean mass.

Finally, any measure of calories will exclude the calories burned repairing muscles so harder workouts burn significantly more than measured. That said, the difference of adding 50% to the time rowed will exceed the calories of rowing faster, hence the advice to row slower longer & more often. Also do what you find is most satiffying at least some of the time as anything is better than the nothing you will do if you give up!

Hope it goes well

Iain

[ukaserex]

SImilar to what others have posted, the C2 monitor has no idea how tall you are, how much you weigh, nor your current cardio-vascular fitness level.

So, if you're rowing 8k in 30 minutes - but you're 6'8" and 270#'s, your calories burned is going to be much different than mine would at 5'10" 215#s.

Even the fitness trackers - Fitbit, Garmin - all they do is slap your personal size/weight/age, slap it into some formula and come up with a guess.

I have a Fitbit Charge 3, and a Myzone HR monitor that I wear when I row. The HR monitor is easily 150% higher than the Fitbit - and the reason why is because the chest strap gets a better measurement. Half the time my HR monitor says 155, my fitbit is still thinking I'm at 110. It's only after a solid 20 minutes of rowing does the fitbit "catch up", and then seems to try to make up for lost time.

First 20 minutes - 120 calories.
next 20 minutes - 265 calories.
last 20 minutes - 395 calories.

So...I don't use any of it, really. I just try to keep my hr in certain zones on certain days. Some days, I fail, because I feel good, and I see no reason why I shouldn't go harder on those days.

The real battle is never on the rower, but in the kitchen.

[jamesg]

Now then, what I'm trying to understand are calories burned as that's one of the main reasons for rowing.

The erg shows average power delivered. If you multiply your average power by time in hours, you get your Work done in W-h and supplied to the machine. Multiply by 4 and call it kCal. So 200W for 30 minutes is 100 Wh delivered, estimated at 400 kCal heat.

You can also track heat by weighing before and after every workout. The sum of the differences x 500 = heat produced. This can be used to calibrate the first method, and of course you see your weight every day.

[iain]

Now then, what I'm trying to understand are calories burned as that's one of the main reasons for rowing.

The erg shows average power delivered. If you multiply your average power by time in hours, you get your Work done in W-h and supplied to the machine. Multiply by 4 and call it kCal. So 200W for 30 minutes is 100 Wh delivered, estimated at 400 kCal heat.

You can also track heat by weighing before and after every workout. The sum of the differences x 500 = heat produced. This can be used to calibrate the first method, and of course you see your weight every day.

I think the above estimate of calories used is an underestimte for anyone who isn't light and rowing efficiently at a low rating. The second formula has an issue as it doesn't discriminate between fluid loss or the different sources of calories (fat has more than double the calories as the same weight of sugars and is associated with less water, so hard workouts that will run on higher proportions of glycogen will appear to burn more calories than they have, although these will continue to increase metabolism and hence weight loss for up to an additional 48 hours.

Basically, best to count calories in to stay honest with eating and measure distance rowed and notice how weight loss varies. If Weight loss slows, eitrher food needs to be further reduced or more rowing done! But the weighing should be at the same time of day and in a similar state of hydration.

[jamesg]

After rowing I need a day, if not more to recover.

Rowing with standard style uses legs, the same as walking. The difference is it's done faster: 150W is pace 2:12, so 3600/132 x 0.5 = 13.6 km/h, while walking is at about 6 km/h on the flat. To generate 150W (150 Nm/s or 15 kgm/s) by walking you'd have to climb a hill at over 700m altitude difference per hour. If not used to it, you'd have a lot of trouble coming downhill too, on a steep path.

Rowing is a good way to put on weight, it works the muscle pretty hard. To lose weight while getting fit and strong by rowing, you have to be fat to start with and then starve. No doubt why I stayed thin at school: little to eat and lots of rowing. Height 6'2, weight (still shown on the blades) 151 lb, 69 kg, age 17. There was more to eat later on, so went up to 12.7 (175, 79kg) and no doubt pulled harder too.

[salty]

At the end of the day, I think monitoring caloric output is an inefficient way to weight loss. Academically interesting, but of limited use in application, IMO. Unless one is a full-time professional athlete, the calories one burns during a workout is miniscule compared to one's total daily output.

Better to strictly monitor intake, by controlling portion size & food choices, if one wants to lose fat. This, I think, will give one the most bang for one's buck. If you don't eat it, you won't have to worry about burning it off. Consider whatever physical activity one does as the "cherry on the top." And all that extra "work" is further incentive not to "mess up" when sitting at the kitchen table.

I didn't mention it but I am on a calorie restricted diet already, and that is definitely helping.

The reason I'm here is that all apps I use to record activity says something about calories. Heck, even the pm5 can show calories burned live so that you can end the activity when you've reached whatever goal you set. Another reason was that rowing was touted as one of the most efficient ways to burn calories, but when I looked at the numbers I didn't quite think that added up for me, so here I am, asking questions, trying to learn.