How beneficial is the strenth to weight ratio on the run?
This question occured to me when Dev Paul commented on an ST thread that runners with a high strength to weight ration do well on hillier courses and finess runners do better on flat courses. I know on the bike in theory absolute power will do better on a flat course and those with a higher wt/kg ratio will do better on a hillier course.
Is there such a thing as w/vdot ratio?
And if there is such an animal how does it effect the run on flat course vs hilly course?
Is there such a thing as w/heat index ratio?
One would think those with higher vdots perform better in flat and cool conditions but is there any adjustment for w/kg or heat under less than ideal conditions relative to just the vdot?
Thanks Tim,
0
Comments
First, I have read that there is a rough relationship between a change in weight leads to a similar change in Vdot (ie a 10% decrease in weight leads to a 10% increase in Vdot).
Second, a lower weight for a given Vdot must make running hills easier and therefore faster — because you need to do less work in the climbing for a given horizontal speed. Coach P reported that with his lower weight this season the hills appear easier to run.
Matt S's heat adjustment material discusses the impact of heat on Vdot for IM run paces that you should read.
Hill running tends to chage your running form and potentially your running efficiency — which could be an important factor.
IMO, running form is something that is worth concentrating on as it is potentially free speed — since getting a Garmine foot pod my running form has improved a fair bit as I now keep my cadance above 90 on every run.
Interesting set of queries!
First, Tim, the smaller one is, the greater the surface area/weight, thus the easier it is to dissipate heat via superficial capillaries in the skin. So you (smaller folk) have an advantage there in the heat over your larger brethren.
Second, I didn't know that strength had a lot to do with running success. East African marathoners don't look like they do a lot of weight lifting. What's a fitness runner? And how does one define strength to weight ratio for a runner - the jist of your questions.
When I look at outstanding elite runners in marathons and Ironman, what I see at the pointiest end is the following: superb running form (all forward, little up and down motion, front/mid foot strike, etc.); lean body mass; thinner calves run faster (less weight to swing forward each step); and obvious fitness combined with a good sense of pace- the winners don't lose form at the end of the race. It doesn't matter if they are going up hill, down dale, or across a windy flat stretch, in the heat, cold or rain.
Just my observations. I don't know anything about how one would try to differentiate among runners to find out who is the strongest/fittest etc except by having a race.
http://www.letsrun.com/2010/heightweight0504.php
or here
http://www.sportsscientists.com/2010/05/sub-27-10km-limit-exclusive-club.html
More generally, by and large, the smaller you are, the better you do in heat.
http://www.sportsscientists.com/2008/05/fatigue-series-part-4-exercise-in-heat.html
@Al....I guess we wont know about the strength to weight ratio of a runner until we can measure power in running. But maybe one could use the w/kg of your bike? But that is what made me thing of the vdot/k ratio? A finesse runner would be a pretty smooth technique runner vs a power or not so pretty gait type runner. Kinda like the description in Ironwar of the difference between Dave and Mark.
@Mike ... Intersting article... Of course there will always be exceptions... Check out this guy Jason Hartman he looks like a giant compared to the Kenyans ..
http://www.mlive.com/sports/grand-rapids/index.ssf/2012/04/jason_hartmann_credits_rockfor.html
I have certainly found that my size and body type does well in the heat. I still suffer but seem to place higher in the high heat races like IMLOU and just recently Boston. However I have not found that correlation to work in my favor in the hilly courses like Mooseman 70.3 even though I have the supposed advantage and a pretty good w/kg ratio.
Also, I'm not sure I'd call VDot a strength indicator, although that concept in running is difficult for me to wrap my head around. To me, it's a predictor variable based on overall fitness.
What goes up must come down. A hilly course will have equal parts up and downhill. Although I'm lighter, I don't go uphill so well, for two reasons: I don't increase my effort level while going up, and I have lost some "power" as I age. Younger folks (which is almost everyone in a race) are always going past me up the hill. Then I fly past them on the way down.
Downhill running is a skill and also may improve with specific strengthening of the quads. I live in a "hollow" with three roads out - all up. So every run includes a lot of downhill running when I'm tired. Even if you aren't so fast going uphill, you may be able to make up the difference on the way down.
I generally agree that being light is a "good" thing, in terms of getting all your weight up a hill or plain running efficiency. I do know of a fair number of "larger" elite runners who are really fast, but I think that's more of an exception to the rule. Elites are at a level of fitness and efficiency that sometimes makes it difficult to compare factors such as weight with the rest of us mere mortals.