Stillman running weight

I first came across the Stillman running weight formula sometime in 2012 although I can no longer find the particularly thorough article in which I first read about it. The formula presumably comes from the pre internet age as I can only find it referred to indirectly online and even then some articles* appear to have been published offline before appearing online.

The formula reflects the simple observation that elite runners are typically lighter than non-runners (of healthy weight) and that as the event distance increases so the athlete tends to be proportionally even lighter. Whether there was any physiological justification of the formula is not clear from the articles I’ve seen; it may be that Dr Stillman derived the formula mathematically to best model the weight of elite runners at the various event distances. I’m writing about the formula not to prescribe a particular running weight as “right”, but purely because I’ve used it to set a personal running weight goal and found using it interesting.

The formula uses imperial units for both weight and height and though I’ve seen the formula re-expressed to use metric units I’ve found it simpler to convert my metric height to feet and inches via Google and subsequently convert the imperial weight value produced to kilogrammes. If imperial units meet all your needs it’s a calculation that can easily be done mentally.

The formula can be expressed concisely in two steps:

Calculate a base value for a healthy, non-active individual by adding 5½ lbs (male) or 5lbs (female) for every inch in height over 5 feet to 110lbs (male) or 100lbs (female).

Modify the base value reducing it by a percentage dictated by event type; sprinters 2½%, hurdlers 6%, middle distance runners 12% and long distance runners 15%.

In my case, a five foot ten inch male, the base value is calculated as:

10 x 5.5 + 110 = 165 lbs = 11 stone 11 lbs = 74.8kg

And modified as below for each event type. [Note  the additional information on what constitutes a sprinter, hurdler etc.]

event type reduction weight BMI
non-active 11 stone 11 lbs 74.8kg 23.7
sprinter (100m – 400m) 2½% 11 stone 7 lbs 73.0kg 23.1
hurdler (100m – 400m) 6% 11 stone 1 lb 70.4kg 22.3
middle-distance (800m – 10K) 12% 10 stone 5 lbs 65.9kg 20.8
long-distance (10 miles plus) 15% 10 stone 0 lbs 63.6kg 20.1

I spent some time considering my racing weight in the context of the formula during early and mid 2012 and in the process decided I was most definitely a middle distance, not a long distance, runner. That is quite likely the case as subsequent performances over 800m, 1500m and one mile would appear to confirm, but at the time it was more in the harsh light of the results produced by the formula. When I first completed the calculation, the goal weight for even a middle distance runner seemed to border on the impossible; I had come close to 70kg / 11st as an adult, but only momentarily. Nonetheless by the time I set my running targets for 2013 I had fixed my goal at 66kg / 10st 5lbs / BMI 20.8.

By August 2012 I’d come close to 70kg / 11st as an adult, but only momentarily.

By August 2012 I had come close to 70kg / 11st as an adult, but only momentarily.

Writing now, within 2kg of my goal weight, it doesn’t seem extreme to any degree; it’s remarkable what a change of position does for perspective. I’ve read that every pound of excess weight lost can be expected to produce a two seconds per mile increase in pace …

event PB weight at PB hypothetical PB
at 66.0kg
800m 2:25.9 71.6kg 2:13.6
1500m 5:18.2 71.2kg 4:56.8
1 mile 5:31.7 73.7kg 5:08.8
5k 18:55 73.5kg 17:13
5 mile 31:36 71.5kg 29:35
10k 39:33 71.6kg 37:00
10 mile 66:41 71.3kg 62:48
half marathon 88:16 73.2kg 81:20

There are some pretty exciting numbers there! I’m looking forward to achieving my goal weight, returning to full fitness after my recent ankle sprain and then rigorously testing out my new physique to see just how much difference it makes.

* See articles at Serpentine and Horwich RMI Harriers club sites.


my running history, a 2012 perspective

[Originally written and posted at parkrunfans blog 10 December 2012]

I was born in the mid sixties and have a few partial memories of secondary school PE lessons including a 1500m, a cross country and being convinced by my schoolmates that I shouldn’t run the 400m in a house competition as another boy – whose name I don’t remember, but whom I can still picture – was a much better runner. He was. And fortunately I listened. These though are one off memories; at school and in the years since it never occurred to me to take up running as a sport or pastime.

I started running some time in 2004 initially mostly on a treadmill. I think I was approaching my 40th birthday at the time. I entered my first race, a 10k, in 2006 and have been entering events and obsessively recording all my running ever since. I’ve raced most distances from 5k to half marathon.

The latter half of 2010 was written off due to problems with my knees and in 2011 I had a seriously debilitating bout of sciatica which resulted in me running only 18 miles that year. I started running again in late February 2012 and half remembered a weekly timed 5k that I’d heard about a few years before. Whether that was a parkrun I was remembering I don’t know, but my searching on the net lead me to parkrun and specifically Dulwich parkrun which I’ve now adopted as my home event even if Crystal Palace parkrun is technically closer. Guess which is the flatter of the two?

I immediately loved the atmosphere and relaxed “feel” at my first parkrun. The seamless combination of serious athletes (running serious times!) and runners of all abilities and ages meant I was hooked. I volunteered within a few weeks of my first run and really enjoyed the experience. Not the most outgoing of people I’ve taken my time getting to know the community, but am getting to know several of the regulars at Dulwich as the weeks pass. At present I work many Saturdays during school terms and so I’m not a week in week out regular myself.

I’m looking forward to 2013, setting new PBs across a range of distances and parkrun being a significant part of that.