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I do a bit of cycling these days, as in nearly 50 km a day.

I do a ring-route. And, there is a mild slope, safe enough to sprint on, and roughly 2 km long with at a worst-case 400 m line of sight visibility without any turn.

By the time I get there, I am a bit tired as I have to climb an ascent to get there.

Should I keep pedaling on such a slope or just sit, steer, control the cycle and then use the momentum in the later part to go another mile or two without much exertion, or should I pedal on the slope so that I can carry on with that momentum over a longer distance.

P.S.: Usually I am not too tired to keep pedaling there. So, I can continue to pedal.

andy256
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WedaPashi
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    In terms of "conservation of energy" you're better off just coasting, and if you were in an endurance event coasting would be the way to go. But you're apparently not, so do whatever works for you. – Daniel R Hicks Oct 09 '14 at 18:22
  • It greatly depends on whether you are racing (or trying to beat a personal mark) or just "need to get there". After that: there is a certain speed above wich it's better to adopt aero position. It must be determined empirically for it depends on circumstances. http://bicycles.stackexchange.com/questions/24372/is-it-preferable-to-pedal-downhill/24375#24375 – Jahaziel Oct 09 '14 at 20:12
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    Yeah, if the downhill slope is sufficient to maintain, say, 15 mph without pedaling then you're probably better off putting most of your energy into maintaining a good aero position rather than trying to pedal faster. – Daniel R Hicks Oct 09 '14 at 21:02

2 Answers2

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Because wind resistance is proportional to velocity squared it takes more power to go from 30 to 32 than from 15 to 17. So you get more bang from your pedal power at lower speeds. If it is a relatively short downhill and you have considerable speed you are typically better off coasting and then pedal when you get to a flat or flatter section.

So you are better off exerting yourself on the lower speed ascent. Then recover on the downhill. It might be 2 minute recovery or 20 minute recovery. If you notice racers typically go all out on the ascent.

If you went up the hill at 8 mph and down the hill at 13 mph compared to a constant 10 mph you would have about 5% more wind resistance.

paparazzo
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I think it is beneficial to pedal hard just on the summit. Although tired from the ascent, pedaling hard for 10 seconds quickly brings one to the target speed. Then one can recover on the downhill (tucking in to reduce air drag).

Failing to do that leads to spending time in very low speed, waiting for gravity to accelerate the rider, and wasting many seconds.

Opinion based MTB riding and no references.

Vorac
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