How much slower do you get from gaining weight?

Your BMI at 6-4, 215 is 26, slightly overweight. It's not a perfect tool, you could be all muscle, so it's just a general guide. I'm sure, long-term, you'll be healthier carrying 215 than 235 or 250 or 300.

As stated above, 1-2 seconds per mile for weight loss, down to the point where you are really lean, then diminishing returns. So if your goal is to get faster, and you drop to, say, 200, you might be about 30 seconds per mile faster.

The main thing is to stick to consistent training and a good diet of healthy foods for the long term. You'll be healthier, and a faster runner as well.

Good luck. I am 56, 6-0, 170 pounds, ran 3;04:42 for a marathon last month, so it can be done. But the most important thing is I am healthy and active. Focus on the long view.

FasttoFattoFast wrote:

It makes a huge difference. I ran in college at 160, 5' 11 with a large frame. I popped off a few Sunday 20 miles at 6:18 pace and it felt good/easy in a flow.

I ballooned all the way up to 234 at my heaviest and 1 mile at that weight felt worse than 20 in college.

I ran a marathon 2015 summer at 200lbs and ran a 3:20. It was 88 degrees which sucked, but I also still could just feel the extra weight making me work more.

I am now training for a marathon in January and trying to aim to be at least 175lbs at the starting line. I plan on going sub 3hrs and will try and remember this thread and let you know if 25lbs made a huge difference.

It will! Good luck

FasttoFattoFast wrote:

I ballooned all the way up to 234 at my heaviest and 1 mile at that weight felt worse than 20 in college.

Sure, but presumably the reason you ballooned was that you weren't running much. Weight gain and not training are obviously often correlated, so you can't exactly run a bunch and then say it was the lost weight that made you run faster. Could be, you know, the running that did that.

So I read through an article someone linked to, and it provided a little extra science to the 2sec/lb rule of thumb. They ran tests on runners performing at their VO2 max at their optimal race weight, and then with additional weights added.

Findings essentially state that for the runners they tested, for every 5% increase in weight, runners ran 90-110 meters less over 12 minutes than at their optimal weight.

Example: For a 215 lb runner whose optimal race weight is 195, a 20:00 5k would convert to something around 18:45 at their optimal weight.

Now I'm getting to the whole point of why I asked the question... It's easy to gauge progression when your weight isn't fluctuating. Being in the process of losing weight complicates the measurement of improvement. I wanted something to help with goal setting

I am 20 lbs heavier now than I was 18 mos ago. Slightly less fit but not far off aerobically today than then. Easy pace then was 9 min per mile. Easy pace now is close to 11 mpm. I'm gonna say most of that 2 min differential is due to weight. Some of it might be due to being older but we're only talking about 18 months here

The extra weight has impacted not just pace, but also duration of runs. I get tired really quickly now

I'm 6"2' I started at 230 lbs and dropped down to 180 in two years. Started with similar times, current Prs are 4:41 mi/17:03 5K/1:24 half(shooting for 1:19 this weekend) the weight makes a HUGE difference just keep at it and watch your diet

Large Fries and a Milkshake wrote:

In addition to my weight, how does my height play a factor in this? Taller people are less efficient as runners for a number of reasons. Would being a tall runner make the situation exponentially worse? Slightly worse?

What was your max mile when you were 230? I am literally about the same size. I can pop a seven minute mile at pretty relaxed effort. Max mile would probably be close to 6 min give or take 10-15 seconds.

Increase in energy cost is directly related to increase in body weight, so a 10% increase in body weight is a 10% increase in the energy required to run...and roughly a 10% slowdown. This generally agrees with the rule of 2 sec per mile per pound, but using percentages gives a more "customizable" result.

Example:

1) A 200 lb runner can run a 6:00 mile

2) gains 20 pounds (10% increase)

3) New mile time: 360 sec + 10% increase = 6:36 mile

This is roughly 1.8 sec per mile per pound

Same example with 150lbs to 170lbs gives 2.4 sec per mile...still generally holds but over a long distance the extra 0.4 will add up.

In your case, at your heaviest you were 38% above previous weight (170 to 235) and the 6:18's you ran became 8:43's just due to weight. Now that you're down to 215, those 6:18's equal just under 8min pace. So I would say it's certainly part weight, but also part lack in fitness.

Losing an added 10-15lbs (roughly 5% of current weight) would give you a drop of 5%. This would make your 10min miles more like 9:30's. Couple that with increased fitness just from continuing to train and I think you'll improve significantly if you keep at it.

Also, the dew point matters. Just wait a few months.

As far as sprinting goes, I have seen that a 2% gain in body fat equates to a 0,.26 increase in the 40 yard dash.

txRUNNERgirl what times are you running these days?

If there are any hills involved you will get a lot slower. It is the injuries u sustain from the extra stress on everything lower back and below that will really slow u down in the end. Weight is your enemy.

Weight makes a huge difference. On top of your aerobic pace being substantially slower as your weight goes up, you won't be able to train as hard because of the increased pounding on your joints. As another poster noted hills are way more difficult.

A 16min 5k runner who is 6ft4 180lbs will really struggle with breaking 20 minutes if thy are 230lbs and somewhat active. The extra weight makes a huge difference.

So I'm 6'7". Leaving college I was 180 pounds and just under 18 for a 5k. I took a sabbatical, went up to 200 lbs, and I could not break 20 at the local turkey trot.

I started running again, got down to 173, and went 17:50 at the same race 2 years later.

Losing the weight made everything about training easier, as others have said.

klubkip1 wrote:

If there are any hills involved you will get a lot slower. It is the injuries u sustain from the extra stress on everything lower back and below that will really slow u down in the end. Weight is your enemy.

I hadn't even taken hills into account. The area in Atlanta I run around has a decent number of long rolling hills. According to Strava, my five mile runs have around 350-400ft elevation gain.

Weight is a huge factor. 2 seconds per pound is probably not accurate for the fitness type like yourself. I am 190 pounds now ( from 210 at heaviest) with huge quads from heavy squatting for 3 or 3.5 years. I ran at 147-150 LBS in HS was in the mid 16's at 50 mpw. Now, after years of running 8-10 miles a week and cycling I finally can run a decent mile. Around 6 mins with comp maybe a bit faster not sure really. I feel and look good pretty good these days. Still lift but not super heavy like before. I could run faster at 175 pounds I'm sure but look good at 190 and have resting heart rate of 60 .

txRUNNERgirl wrote:

Here's a rule of thumb: you'll weigh less if you cut off your thumb. Even less if you cut off your arm.

There are many other things that will make you fast other than weight. I'm faster now than when I was 20 pounds lighter.

I'll echo this sentiment. I gained the 'freshman 15' during my first year of college, but it all came from weight lifting more seriously, eating a lot more, and was in spite of an increase in mileage. I'm sure lots of factors produced my increased ability that year, but I am convinced that increasing my muscle mass was among them. My speed workouts and mid-distance PRs all dropped dramatically. Weight loss is helpful is you're losing dead weight, but below a certain point if you're losing mass in the form of muscle catabolism, you're chipping away at the engine that drives that ever-lighter frame. There's such a thing as "too skinny."