Will weighing three extra pounds...

Sheeit, 3 pounds? That's just daily variation.

Surely that should read differently.

"eating good" should be "eating well".

The reason being, you are quoting a phrase, "eating well", not speech.

If we look at the elite women at the head of a marathon field, for an example, their weight will vary by 1,2 or 3 lbs depending on the day, typically. It's not possible to be EXACTLY the same weight every single race day (by this I mean to the exact lb). Their times are fairly consistent, I could bring in a lot of examples but I'm not going to bother typing them out.. put it this way, it would be a shock to see some of them finish 2:37 down (6 seconds per mile slower, for 3lbs more weight) and is usually attributable to other factors (injury, illness) by their coaches if one of them runs badly, not a slight difference in weight. Now say if it was 10lbs, that's more of a likely factor.

The other thing is, these equations only hold true if it's true weight.. as in, your power/weight ratio hasn't changed.. it's 3lbs of deadweight vs muscle, many other factors.

I calculated the theoretical performance assuming weight/time ratio. This shows that the 15:50 was the best time indicating improved efficiency or power/weight ratio. Assuming the same power/weight ratio and efficiency as in the 21:50 5K would result in a 17:02 5K time at 160 lbs.

Using the same method it's easy to calculate that a 160 lbs, 15:50 runner would run 16:08 at 163 lbs and a 160 lbs 17:02 runner would run 17:22 at 163 lbs. There is no reason to assume this is not true, however there are other factors (wind, competition, temperature, terrain) that cause larger differences between races.

weight time theory theory

215 0:22:39 0:21:17 0:22:54

205 0:21:50 0:20:17 0:21:50

195 0:19:40 0:19:18 0:20:46

190 0:19:00 0:18:48 0:20:14

185 0:18:30 0:18:18 0:19:42

180 0:18:00 0:17:49 0:19:10

175 0:17:30 0:17:19 0:18:38

170 0:17:00 0:16:49 0:18:06

167 0:16:40 0:16:32 0:17:47

160 0:15:50 0:15:50 0:17:02

163 0:16:08 0:17:22

I meant to say assuming weight/time ratio is constant

Another error:

The calculations in the table are based on the assumption that power is the same not power/weight ratio. The decreased power weight ratio is what explains deteriorated performance.

If you lose weight, does your power/weight ratio have to increase for your performance to increase?

Stop bitching about weight, u women!

The whole idea behind the calculation is that power remains the same with the weight change.

It's the same for both men and women: 1% weight gain results in a 1% slower time/speed when the same power can still be produced.

Usually, with weight gain, more power can be produced, therefore the difference will be less.

So your power/weight ratio is increasing, which is what makes for the better times?

But only if the same power can be produced at the lighter weight.

FWIW I put on about 8 lbs of muscle from lifting and my 10K has gone from low-33:00 to 35:00 (same training). However my mile is about the same and my 800 somewhat faster (I have better last 200 kick). Oh yeah and better-looking girls to date.

"These times are aproximate I can supply links to exact times to back this up if you don't believe me"

I call b.s. until you show the proof

So this guy lost 7 lbs (from 167 to 160) and dropped 50 seconds from his 5k?

The problem is, we don't know what else he kept constant or changed.. it's all too complicated

I haven't checked the board for a while sorry for the delay.

As others pointed out my fitness level has changed so I guess this isn't proof of 2 seconds per mile per extra lb.

But anyways here is my info (I can't prove my weight so I guess you can take that with a grain of salt)

Here are my results:

215 lbs 22:30 place: 36 (My name is listed wrong as 'Scott Rouie')

http://www.coolrunning.com/results/03/nh/May4_Rotary_set1.shtml

205 lbs 20:56 place 171

http://www.coolrunning.com/results/03/nh/May25_Runner_set1.shtml

195 lbs 19:29 place 16

http://www.coolrunning.com/results/03/nh/Jul26_5thAnn_set1.shtml

192 lbs 19:16 place 195

http://www.coolrunning.com/results/03/nh/Aug14_CIGNAH_set1.shtml

187 lbs 18:49 place 110

http://www.coolrunning.com/results/03/me/Sep27_EliotF_set1.shtml

185 lbs 18:37 place 24

http://www.coolrunning.com/results/03/nh/Nov8_BruceE_set1.shtml

185 lbs 18:28 place 3

http://www.coolrunning.com/results/04/nh/May2_14thAn_set1.shtml

179lbs 18:01 place 33

http://www.coolrunning.com/results/04/nh/May30_Runner_set1.shtml

172 lbs 17:15 place 34

http://www.coolrunning.com/results/04/ny/Jul31_SilksS_set1.shtml

170 lbs 16:55 place 11 (race was on a outdoor track)

http://www.coolrunning.com/results/04/nh/Aug27_LOCOSe_set1.shtml

167 lbs 16:43 place 6

http://www.coolrunning.com/results/04/nh/Oct24_WayHom_set1.shtml

165 lbs 10k 34:24 place 1 (equivalent to ~16:30)

http://www.coolrunning.com/results/04/nh/Nov25_Freefa_set2.shtml

I am at 160lbs now I haven't raced an official 5k this Winter.

I have done a few workouts that make me think I am at 15:50 shape (however I don't have proof so perhaps I shouldn't have stated it):

I did a tempo 5k on the track at 16:06 (I ran hard but not all out)

A 2x 2mile in 10:20 with 4 mins rest.

I will be running Boston Prep 16 miler next weekend but that would be a stretch to extrapolate my 5k from that.

The last 2 months I have been averaging 90 miles per week ranging from 120miles to 70 miles a week. Previously I was averaging closer to 70 miles a week.

As others have pointed out 3lbs can be daily variation and my example is over the course of almost 2 years, so I don't think this info can be used for the original posters question. I apologize for the sidetrack.

Ok, I'm impressed now (and yes, I'm quite certain you could run 15:50). That's an amazing improvement.

When you ran the 22:30 5K at 215 lbs, how long had you been running for? Did you run in college and then take a layoff in your early to mid 20's?

What is a typical 90 mile week for you? How many speed workouts? training paces?

I recommend you pull all your teeth and shave all the hair on your body and definitely run naked. Anywhere you can shave a pound off will definitely help.

goodness wrote:

2 seconds per pound for every mile,roughly.

I'm sure your fitness didn't increase at all during this progression. I'm sure it was just your weight, right?

When I ran 22:30 I was coming off a 5 year break from running (during which I gained 70 lbs). I had run for only a few weeks before the 22:30 race.Previously I was a mediocre DIII college runner 5k pr 15:14. In college I typically weighted about 145 lbs and didn't run high mileage (about 40 to 70 miles a week). I had many problems with my hamstring after I pulled it early my sophomore year.2003 to 2004 My training was erratic. I hurt my hamstring a few times from going too hard in speed workouts.2004 to 2005 I buckled down and just put the mileage in. I only added speed work after I got a 10 week base of 50MPW. I found the higher mileage and hill workouts on Tuesday strengthened my hamstring so I could do speed work without hurting myself.A typical week now is:Monday: 15 miles easy (~6:40 pace)Tuesday: 10 miles (5 up a pretty tough hill, 5 down)Wednesday: Morning: 5 to 10 miles medium/hard effort ( ~6:10 pace) Evening: 4 miles of intervals or tempo work on the track. 4 miles of jogging/strides.Thursday: 10 miles easy (7 to 6:40 pace)Friday: 15 miles easy (~6:30 to 6:40 pace)Saturday: Morning: Long progression run 15 to 20 miles (Start ~7:30 pace increase to ~6:10 pace) Evening: 5 to 10 miles easy (~7:00 pace)Sunday: 10 to 15 miles easy (~6:40 pace)During the spring/summer I plan on adding a 2nd speed workout Saturday or Sunday if I don't have a weekend race.I don't follow a schedule strictly. If I feel good on a certain day I will go hard. If I feel tired I will go slow and just log the miles. I plan on targeting my first marathon next fall If I can drop 10 to 15 more pounds. Any suggestions on how I should adjust my training leading up to a fall marathon would be appreciated.

Please do... wrote:

Ok, I'm impressed now (and yes, I'm quite certain you could run 15:50). That's an amazing improvement.

When you ran the 22:30 5K at 215 lbs, how long had you been running for? Did you run in college and then take a layoff in your early to mid 20's?

What is a typical 90 mile week for you? How many speed workouts? training paces?

In response to indirect correlation.

Your point is taken. I am sure my fitness level has changed, therefore the effect weight loss has had on my times is unclear.