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#1 |
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Junior Member
Join Date: Jun 2003
Posts: 27
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On a descent today (14.4%) I managed to get a speed of 49.7 mph as it was leveling about I passed some guy on his trek with full team apparel (including baseball hat!) begining the climb. I spun the bike round and gave chase...he was about 75 ft ahead of me. I managed to catch and overtake him and beat him to the top by about 60 ft.
while I was pleased with my 'victory' I began to wonder how I could get faster up such hills. the hill is about 1.2 miles long and I was in the saddle for about 90% of the time. The climb took me about 5mins 15 secs and I think I averaged about 13mph, however, I would like to know how I can improve on this. Can someone give me some advice on the type of training I need to do in order to better this time. Thanks. |
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#2 | |
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Registered User
Join Date: May 2003
Location: Victoria, Australia
Posts: 88
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Quote:
According to my rough calculations, if the hill was really 14.4% average grade and you climbed it at 13mph, you were putting out around 600+ watts over your 5 minute ascent! So you don't need to get any better, you need to contact your local Olympic team and get yourself registered for the track individual pursuit event, pronto. However I suspect at least one of your figures is suspect, probably the gradient number. 1.2 miles at 14.4% would be one extremely steep mutha of a hill. Even the pros would be climbing that one in 39*23 or smaller. Last edited by Unregistered : 01-07.-2003 at 01:51 PM. |
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#3 |
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Junior Member
Join Date: Jun 2003
Posts: 27
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I was climbing the hill in 39x23! I know the gradients is correct - I have calculated it on two fronts - firstly by using an Ordnance Survey explorer map and secondly by using polar software (information upload from a 720i
Would you mind giving me your calculations for Wattage output? If it really is about 600W then I would be putting out 8.9W/KG, which I'm informed is quite a figure. Many thanks. |
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#4 | |
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Community Team
Join Date: Nov 2002
Location: Newport, South Wales
Posts: 3,830
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Quote:
To get an excellent ball park figure for power output, go to www.analyticcycling.com. Using your figures, 67.4 kg; 14.4% grade and a velocity of 13 mph i get an approximate power output of 686 W. Managing this for 5mins 15secs would be beyond the limits of human endurance by a long way. The world pursuit record set by Boardman in 96 (for what 4min 11secs???) works out at an average of 520 W. I guess one of your figures must be out! either speed or grade. Ric
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#5 | |
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Registered User
Join Date: May 2003
Location: Victoria, Australia
Posts: 88
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Quote:
Ric's undoubtedly given a more accurate figure. All I did was work out the power required to overcome gravity, which you can calculate as : M * g * v * r where M = mass of rider + bike (kilograms) = (guess) 65 + 9 = 74 kg g = gravitational acceleration at earth's surface = 9.81 m/s/s v = speed (metres / s) = 13 * 1600 / 3600 = 5.78 m/s r = gradient = 0.144 yielding Power (climb) = 74 * 9.81 * 5.78 * .144 = 604 watts In addition to this, as Ric's calculation shows, there are some watts needed to overcome air resistance, rolling resistance etc. If your 720i and the PPP software is saying 14.4% then I think your altitude readings are haywire for some reason. If it was the distance measurement (eg setting up the wheel circumference way too large) you'd also be seeing impossibly high speeds on the flat. You could double check this by using the following alternative formula for power which doesn't depend on gradient or speed: P (climb) = altitude gain (metres) * M * g / climb time (seconds) If your 600+ watt figure were right (which it obviously cannot be, as per Ric's note), then given it took you 315 seconds to climb the hill, the height gain would be 260 m or 853 feet. Assuming you're putting out a somewhat less superhuman figure of 350 watts (still pretty damn good), the height gain would be less than 150 m / 500 ft. One final thought - you're not by any chance calculating gradient using different units for height gained vs distance travelled? Last edited by Unregistered : 02-07.-2003 at 12:25 AM. |
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#6 |
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Junior Member
Join Date: Jun 2003
Posts: 27
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thanks for the replies.
I used metric units in all calculations. Polar 720i is adjusted before every ride to accomidate deviation from SLP. Anyhow, now i've got the answer to working the calculation - back to my original question - how do I get fast - good workout suggestions, please? Thanks. |
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#7 |
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Moderator
Join Date: Feb 2002
Location: UK
Posts: 1,265
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Given that you want to ride a hill 5 minutes long, you need to raise your VO2 max. Shorter hills <60 secs you need to increase your aerobic capacity and >8 minutes your lactate threshold.
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#8 | |
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Community Team
Join Date: Nov 2002
Location: Newport, South Wales
Posts: 3,830
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Quote:
Unregistered, to arrive at my estimate of power i just used analytic cycling web site. i used a slightly greater mass, because james will presumably (i hope!!) be clothed and have drinks bottles on. Even at 350 W and 65 kg mass for james, that gives a power to mass ratio of 5.4 W/kg, which for that duration (~ 5 mins) will certainly start sorting people out! Ric
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#9 |
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Junior Member
Join Date: Jun 2003
Posts: 27
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how long would a pro rider be able to sustain his VO2 max for? Close by to where I live there is a hill (4.6%) that runs for about 2.5miles. I have calculated using the analytical cycling web site that in order to produce the same power (per kg) as lance I would have to 'scale' it at 23.3mph. I'm not saying I would ever be able to achieve it, however, goal setting is surely good for one!
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#10 | |
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Community Team
Join Date: Nov 2002
Location: Newport, South Wales
Posts: 3,830
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Quote:
James, Not sure what figures you are using for power to mass for LA, but using 23.3 mph and a mass of ~65 kg for yourself, i get a power requirement of ~567 W, which is 8.7 W/kg. I'm not entirely sure what you're trying to do? When you say VO2 max, do you mean the VO2 max itself, the power at the end of an incremental test to exhaustion (MAP), or the minimum power required to elicit VO2 max? Ric
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#11 |
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Junior Member
Join Date: Jun 2003
Posts: 27
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Ric -
Thanks for the reply. I'm trying to increase my Wattage per KG, hence hit into the pro cycling arena - maybe a long shot? Re VO2 Max: I was wondering if this was in reference to sustainable power. Also, I'm interested in getting some coaching, best to take this offline? |
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#12 | |
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Community Team
Join Date: Nov 2002
Location: Newport, South Wales
Posts: 3,830
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Quote:
James, Where i've mentioned sustainable power, i'm refering to power that can you maximally sustain for a long period of time (e.g., TT power for 30/60-mins) Testing would determine whether you're currently anywhere near pro standard (as would racing, but not as objectively). Please give me a shout at ric@cyclecoach.com, cheers ric
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