Weights in backpack ?

mr_eddy

Realistically how much extra in terms of calories burned does carrying say 10kg of stuff everyday in a back pack compared to not taking a backpack (with all other variables being equal).

I am trying to increase the calories burned on my commute to work and increasing the weight in my backpack is the simplest/cheapest option I can think of (increasing speed / distance is not an option and I use a SS with a set gear inch which I am not willing to change).

I have fitted fatter winter tyres which has made me sweat a bit more but they are as wide as I dare on my road frame.

jgsi

Rucksacks for roadies are the very works of the devil.. nasty .. just nasty.. if I do use one, riding to a local summer race, it has at the most, 2 to 3kg.
#justpedalharder
#calorieburn
#encylopaediasinpanniers

mr_eddy

I know they make your back sweaty etc, but realistically its the only way I can increase the effort required on my commute without either a) spending money b) increasing my ride time c) pedalling faster. I cannot increase the distance and given that I cycle in heavy traffic both ways I cannot realistically increase the speed either. I have tried dropping my tyre pressures a bit but that just encourages pinch flats. I am happy to to stick my heavy duty chain lock in my bag (this would add 5kg to my normal backpack stuff) but it its only going to add 100 extra calories to the amount burned then I will just find another way

mr_eddy

Should add for reference my ride is 4 miles each way with 2x200m low gradient climbs each way. I ride a road bike with 48x16t gearing and 28c tyres (my brakes won't take anything bigger). I just want to increase my calorie burn to maybe 300 extra per day so as to help shed some more weight, Also I am thinking that the extra weight will make my nice road bike feel so much better when it comes back round to the spring sportives

mr_eddy

Panniers maybe an option as JGSI suggested, I will check to see if my bike as pannier mounts - Obviously this would involve spending money which I wanted to avoid but maybe I can pick up something cheap on Fleabay

ai_1

It's impossible to accurately answer your question.
However, I wouldn't expect an increase in weight of ~10kg to make a significant difference on flat roads. The biggest increase in energy expended would probably be the effort of supporting the weight on your shoulders rather than cycling effort. There would be a minor but probably insignificant increase in rolling resistance. Speaking of which, why do you think the 28mm tyres have increased your energy use? They will not necessarily have increased rolling resistance just perhaps a minor increase in aerodynamic drag.
I would say the two 200m small gradient hills aren't enough to make you work noticeably harder due to the extra weight.

jgsi

For under a tenner, you could get a 14t track sprocket.. that will make you work harder than your current gearing.

mr_eddy

Yep another option I suppose.

xscreamsuk

why can't you extend the commute?

ai_1

Incidentally, from past experience my Garmin typically estimates about 25 calories used per kilometer on non-mountainous routes. That's about 40 per mile or 160 each way for me. The figure may vary slightly for you and your bike and this is only a Garmin estimate but it should be in the right vicinity. So, if you're probably only using in the region of 160 calories each way (320 total) at the moment it's a hell of a big ask to increase this by 300 calories without making some pretty substantial changes. Could you just add an additional 8 miles onto your ride home in the evening perhaps?

The only simple bike mod I can think of that would do the trick is to set the brakes up to rub slightly on the rims. This would certainly increase resistance but the bike would be horrible to cycle and you'd probably give it up pretty quickly. It would also wear out the brakes and rims in short order and require regular adjustment. I wouldn't do it.
Anything that increases the calories used without you taking longer to do the ride is also going to increase the intensity of the ride of course. So prepare to be much sweatier. Seriously, I'd just add mileage at the start or end of the day. That way you at least wouldn't start to hate cycling which your current plan sounds likely to result in.

slowbike

air resistance would be your best bet - add a trailer and a big flappy mac. Perhaps you could put a pointy santa hat on your helmet too ...

10Kg in a backpack wouldn't make huge amounts of difference - 4 miles each way is not even a warm up - if you want to double your calorie burn then double the mileage.

Or eat less ...

dodgy

Just drop 300 calories from your daily food intake.

pan280

how long is your commute? running burns more calories so you can either run all the way or if you want to burn even more, run with the bike!

meanredspider

As above, unless your route is hilly, weight is the least effective way of increasing load. Baggies and a flappy jacket whilst sitting as upright as possible. Then get some cheap, nasty heavy wide tyres and under-inflate them.

Or just ride further and enjoy it more.

CptKernow

Water bottle full of small change?!

frisbee

I don't really notice my rucksack, even with the 5kg turkey I was carrying home tonight.

Take your saddle (and seatpost!) off and ride out of saddle?

DavidJB

frisbee wrote:

I don't really notice my rucksack, even with the 5kg turkey I was carrying home tonight.

Take your saddle (and seatpost!) off and ride out of saddle?

Putting 10-15kg on my back makes a huge difference when climbing for me...but it's basically adding 1/6th of my body weight on...plus I commute on my cross bike.

Even when I take out my Kinesis racelight at the weekends after it sitting on the turbo in the week it feels like a super light flying machine...can't wait to get on the race bike again!

gavbarron

Sprints between lights or every time traffic clears put the hammer down as hard as you can, a HIIT types commute would burn more calories than extra weight whilst just bumbling along which I doubt would add very much extra calorie consumption.

bahzob

The best way to find out what works would be to use some sort of independent measure to determine how hard you are exercising. Fitting a power meter for a 4 mile commute is a bit OTT but a simple HR monitor will give you the info you need. Averaged over a number of rides (to exclude the effects of any outliers) the higher the HR the more calories you will be burning. You will answer your own question simply by doing a few rides, one with the bag other without. If the bag doesn't add 5+bpm its probably not worth the hassle.

Of the above suggestions, if safe, I would agree that doing some really hard short sprints is probably the best idea. Apart from burning calories it is also the only way you can really improve fitness on such a short ride and this will pay off by allowing you to ride at a higher rate>burn more calories when doing longer workouts. If you do this HR is not so useful though if you do a ride with sprints at the same average HR as a steady one then you will for sure have worked a lot harder.

iPete

4 miles, run to work.

Don't put a bigger gear on, I doubt you'll burn more calories grinding vs spinning a higher cadence.
If anything, put a smaller gear on and change to fixed.

ai_1

iPete wrote:

....Don't put a bigger gear on, I doubt you'll burn more calories grinding vs spinning a higher cadence....

Agreed. In fact spinning should in theory utilise more energy than grinding since you're doing more work (assuming the same bike speed you're expending more energy moving your legs and the same amount moving the bike. Your muscles get an easier time but your CV system does more work and you'll be using more energy. This is why you typically have a higher HR when spinning. the advantage of spinning is in muscle fatigue, not energy efficiency).

Matthewfalle

CptKernow wrote:

Water bottle full of small change?!

I used to use two large water bottles filled with damp sand - roughly 1 1/2 kilo each. Does the job perfectly - central to centre of gravity, cost nothing, real training gain.

ai_1

Matthewfalle wrote:

CptKernow wrote:

Water bottle full of small change?!

I used to use two large water bottles filled with damp sand - roughly 1 1/2 kilo each. Does the job perfectly - central to centre of gravity, cost nothing, real training gain.

I don't really see the point. Was this for short hill training sessions or what?
You're only adding s very small proportional increase to bike weight, losing your bottle carrying ability and you could surely achieve the same by just climbing a tiny bit faster?

cougie

300 calories is the effort needed to run about 3 miles for the average sized bloke. I cant see how you could do that extra over a 8 mile distance. Its probably only 300 calories you're using for that - so unless you do it twice....

If its for losing weight - far easier to eat a bit less.

If its for a difference when you swap to your racing bike - well you only notice it for about half a ride and then its back to normal

If you can run - do that - maybe alternate running with cycling ?

Matthewfalle

Ai_1 wrote:

Matthewfalle wrote:

CptKernow wrote:

Water bottle full of small change?!

I used to use two large water bottles filled with damp sand - roughly 1 1/2 kilo each. Does the job perfectly - central to centre of gravity, cost nothing, real training gain.

I don't really see the point. Was this for short hill training sessions or what?
You're only adding s very small proportional increase to bike weight, losing your bottle carrying ability and you could surely achieve the same by just climbing a tiny bit faster?

Negative - used on "smash yourself to bits" commute (15 miles witha couple of bugger step hills) and lunchtime "smash yourself to bits" rides - not long enough to need a water bottle but long enough to get strong as.

You're riding as fast as you possibly can and the extra weight, imho, helps.

I personally felt the benefit of doing that for a winter/spring then jumping on the super light race bike.

bobmcstuff

Running would definitely burn more calories if that's what you're really interested in.

mangetout_rodney

Weighted backpacks can help a bit with running but cycling it isn't going to make much of a difference.
Up the intensity, do intervals, cycle a longer route instead.