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I have bought a weight vest, 10kg. I am wondering if it will help me burn more fat during a bike riding?

Logically, it makes sense, but someone told me our body would become used to this new body weight and adjust itself accordingly so that this increase in calorie burning will gradually wear off over time.

Thanks

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    If you have panniers on your bike, an alternative is to put bottles of water in them. That way, if you decide half way round the weight is too much, you can pour the water out. – paj28 Sep 14 '16 at 9:32
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    Or drink it, if you're in the woods and there is no shops around. (0: – CopperKettle Sep 14 '16 at 12:13
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Depends on the distance you are biking. Always use the physics behind every workout, to calculate the load, or calorie burn. In your example, you are adding 10 kgs to the weight of you bike.

When you are biking on a flat surface, majority of the work is done is against friction between the road and bike's tires. The force of friction is uR where u is the coefficient of friction and R is normal reaction, which is your weight+ that of bike and added 10 kgs.

Work done is force x displacement, so any added weight is going to make it count when it comes to calorie burn.

Also, when you go uphill, you are doing work not only against friction, but the downward pull due to the gravity as well.

Body may become used to it in time, but by the time it will be in better shape than what you started with.

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    +1 Good use of physics in your answer! Definitely worth noting that the training done will not transfer perfectly into extra-speedy time trials with lycra and a carbon bike. OP will just get very good at moving a heavy bike. – Gunge Sep 14 '16 at 7:04
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    Most work on a bike is air resistance at any decent speed on the flat: bicycles.stackexchange.com/a/38182/7309 and it's link. This is independent of weight, so you're probably better off adding drag (big panniers) – Chris H Sep 14 '16 at 8:01
  • "majority of the work is done is against friction between the road and bike's tires": This depends a lot on the speed. For slow speeds it's true; for speeds faster than about 17 km/h (that is, for most of us) air resistance or drag becomes the predominant force because it grows quadratic with the speed. – Peter - Reinstate Monica Sep 14 '16 at 14:41
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    Regarding adding weight - put it on the bike. Putting it on yourself increases impact if you fall. – Blackbeagle Sep 14 '16 at 21:56
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    @xCodeZone. You are technically correct (espcially as you imply the coefficient of drag plays a role not jut the area). The question said "weight vest" which would have hardly any effect on the cross-section: at least looking at a random selection on amazon, all the weight is front and back, so no width is added. – Chris H Sep 15 '16 at 7:45
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What they told you actually make sense in some contexts. The only way you could consume less calories with added physiological work is if you develop economicity in your motor skill.

To be more clear, architecture of type I fibers allow you to produce less power stroke in the architecture of sliding filaments but at longer leghts compared to type II fibers.

With this you can actually mantain a certain pace exploiting the viscous properties of the type I fibers along with their architecture and their chemical features ( phosphorylated ATP stays longer on type I myosin heads as ADP, that's one key characteristic that make these fibers less susceptibles to stretch/strain and suitable to work at higher lenghts ).

However, the moment you add weight to yourself, you actually will do more physiological work no matter what. The fact that you can develp efficiency doesn't mean you will consume the same amount of calories no matter how much work and weight you add to your routine; this just make no logical sense at all.

To answer your question: no.

Adding 10kg to yourself will not help you burn more fat, or anything else. Burning fat is for a large part depends on the actual total time or/and intensity of work.

You could go at a low intensity for a very long amount of time, and you will burn fats ( this is highly variable upon individuals and training level/muscle cell phenotypization ). Or you could go at a high intensity for intermittent intervals and build a very big EPOC that will help you burn fats while you recover ( remember that RER - Respiratory Exchange Ratio, drops at 0.7 after high intesity exercise ); for this, is better dynamic exercise ( like cycling ) instead of static exercise ( like weightlifting ).

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I don't want to debate the correctness of the accepted answer, the heavier you are the more energy you need to invest to build up and maintain speed. However, saying that the majority of the work is done against friction is not correct at all.

Air Drag

On a flat road, aerodynamic drag is by far the greatest barrier to a cyclist's speed, accounting for 70 to 90 percent of the resistance felt when pedaling

Source

Bicycles are very inefficient when it comes to Aerodynamics, as this Wikipedia article illustrates.

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    This is the correct answer. If you want to burn more calories, ride faster (duh) or increase drag at the given speed, e.g. through wide, flapping clothing. – Peter - Reinstate Monica Sep 14 '16 at 14:43
  • "However, saying that the majority of the work is done against friction is not correct at all." In my answer, I have also included slopes, and the weight theory. Your answer holds valid when you are biking at high speed. At low speed or average speed, it's the friction, unless you gave the wind against you. – xCodeZone Sep 15 '16 at 0:26
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    @xCodeZone this diagram does not validate your statement. I'd say 20Km/h is pretty average, and at that speed air drag already outweigh friction by more or less 2:1. Obviously slopes are another matter, but even there friction is only marginally important. Just look at the diagram, it's pretty straight forward. – r41n Sep 15 '16 at 9:02
  • @r41n: with all respect for the diagram you have posted, what's the source of it, and under what conditions was the test conducted? There are several factors involved. 20Km/h is not average, it's above average. Even if we take the graph under consideration, till 15 km/h it's rolling friction that dominates. – xCodeZone Sep 15 '16 at 23:10
  • @xCodeZone, I don't mean to debate this. I never heard of friction being the dominant force in biking, it always was Air drag, and all my listed sources state the same thing. The diagram is from the Wikipedia article in my answer. Anyway, this is "fitness" related, and average cruise speeds of 20-25Km/h are the norm for any person which bikes regularly for fitness. I managed sprints of 50-55Km/h and averages of 20-25Km/h when I was 13, and I was using a MTB, not a street bike. – r41n Sep 16 '16 at 7:21
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As stated by r41n,

On a flat road, aerodynamic drag is by far the greatest barrier to a cyclist's speed, accounting for 70 to 90 percent of the resistance felt when pedaling.

I've witnessed several cyclists who wear small, controllable "parachutes" to vastly increase resistance the faster they are going. Bike Parachutes

This, (next to uphill training in mountains), is one of the best "boosts" to your cycling workout, as it is fairly consistent (unlike mountain/hill training, with varying gradients).

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No.

If you are already riding at a certain intensity (power) the weight will only make you slower when accelerating or riding uphill. E.g.: If you are capable of outputting 200W for an hour (and riding at that power) that output power and thus calorie consumption won’t change, you’ll just be slower.

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Take the advice of Eddy Merckx, "Ride lots".

More weight == more work, plain and simple, unless you are coasting downhill all the time. How much benefit (i.e.: weight loss) the extra work will get you depends on any number of factors.

The top level Tour competitors are, in one respect, in a "grams per bike" competition. Lightening the load they have to move down the road, or up the mountain means less energy expended getting to the finish, which means a better chance for a podium finish, all other things being equal (which they never are -- people vary).

Riding with that extra weight once a week for a short period will probably just get you sore legs once a week. Riding with that extra weight for an extended period multiple times per week (3 or more?) should yield more weight loss. Your body reacts to the demands placed upon it.

If calorie intake isn't changed while the workload increases, yes, your body will become more "efficient" and store more intake as "ready calories", because it expects to need them available. Over time, an "intake to work" equilibrium might be reached, but that doesn't diminish the benefit of the extra weight/extra work.

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No, and it might even make you burn fewer calories!

The power (energy per second) that you put into cycling is spent in two ways:

  • Overcoming "rolling resistance" (e.g. flexing the tires)
  • Overcoming "wind resistance"

At about 20 km/hour and above, "wind resistance" is the larger/dominating term. It increases as the square of the speed (so, e.g. to increase your speed by 20% would require 45% more power).

Anyway, the canonical way to spend more power into a bicycle is to travel faster.

To go faster you might want to pedal more rapidly in a lower gear (the "cadence" of your pedalling should definitely be above 60 cycles per minute ... maybe 90 or more with practice and with clips or cleats on your cycling shoes). It's better to spin faster with medium force that spin slower with big force ... if the pedal-spinning slows below 60/minute then you need a lower gear.

Anyway, once you're cycling (after you've warmed up, e.g. after the first 20 minutes) you ought to be getting wet, either because it's raining or because you're sweating. Generally you'll be hot and sweating. One of the things that makes cycling bearable (or pleasant) is that there's always a wind when you're cycling ... and that wind helps to keep you cool. Cyclists wear "moisture-wicking" clothing which helps to keep them cool (helps sweat to evaporate).

One of the limits, one of the things which may limit how much work you do, is how hot you get and how quickly you can shed that heat. Imagine: you could work harder in a hot gym in front of a cooling fan than you could without the wind from the fan. Similarly you can bike harder if you don't get too hot, and if you start to get too hot then you have to stop or slow down (or risk heat stroke etc.).

So, don't wear a "weight vest" which would keep the heat in and not transpire. Wear lightweight clothing and cycle faster.

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