I love wearing them; I suppose it’s a fetish and it’s my secret life. I even wear my wife’s. They’re always clean but Michelle is smaller than me so it’s a tight squeeze. I just like how they feel and look. I never wear them all day, well almost never. I certainly haven’t discussed this with her. Sometimes she complains about them being stretched and out of shape after I borrow them. But I say nothing. I’ve even made trips to the shop in them, because mine tend to get soiled when I’m out running. But nobody has noticed. I don’t exercise in them; I haven’t tried, because to be honest, I think it may hurt. I just like to wear them casually, just for fun. It has always seemed unfair that women have lovely colours and designs to choose from, while men have such a limited choice. She has nearly caught me so many times; she has noticed the occasional odd walk. But now she knows I do it all the time, I borrow her of runners! Only because mine are destroyed from running in mud and grass and dirt. I hate it; it upsets me to see a lovely pair of runners destroyed. But apparently running on the grass is better than running on hard roads, because softer ground protects the body from injuries……. Or does it? Whilst there is evidence that running on harder surfaces increases the impact force when the foot hits the ground (Kerdok et al., 2002), there are no comprehensive scientific studies that show a link between the hardness of a surface athletes train on and injury rates (Marti et al., 1988; Taunton et al., 2003; van Gent et al., 2007).
Road running has long been vilified, and described as brutal, resulting in joggers being left on the scrap heap requiring joint replacements early in life. So why do so many think a soft surface is more forgiving on limbs. Is it another example of trusting the accepted norm rather than questioning conventional wisdom? It seems obvious that the impact of running on hard concrete is greater than running on grass, but why are injury rates not affected? The reason has been proven time and time again, the body automatically adapts to changes in running surface. Rapid adjustment in leg stiffness facilitates the smooth transition between surfaces of different firmness. The body anticipates the stiffness of the running surface and adjusts how strongly the leg muscles contract in preparation for impact. This allows the body to pre-tune the legs differently when stepping from concrete onto grass. Strangely when running on a hard surface the legs are less stiff than they are on a soft surface (Ferris et al., 1999) Both high and low leg stiffness caused by running on the different surfaces have been linked to increasing the risk of injury (Nigg, 2001; Butler et al., 2003)so which surface is responsible for causing injuries – who knows? The apparent lack evidence in identifying the role of training surfaces in causing injuries may stem from the difficulty in effectively measuring the time and intensity of running spent on each of the running surfaces (Taunton et al., 2003). So with no evidence that running on softer surfaces prevents injuries, there is no reason for me to sacrifice my runners any more. But I’ll still keep wearing Michelle’s, just because I like to.
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Ferris DP, Liang K & Farley CT. (1999). Runners adjust leg stiffness for their first step on a new running surface. J Biomech 32, 787-794.
Kerdok AE, Biewener AA, McMahon TA, Weyand PG & Herr HM. (2002). Energetics and mechanics of human running on surfaces of different stiffnesses. J Appl Physiol (1985) 92, 469-478.
Marti B, Vader JP, Minder CE & Abelin T. (1988). On the epidemiology of running injuries. The 1984 Bern Grand-Prix study. Am J Sports Med 16, 285-294.
Nigg BM. (2001). The role of impact forces and foot pronation: a new paradigm. Clin J Sport Med 11, 2-9.
Taunton JE, Ryan MB, Clement DB, McKenzie DC, Lloyd-Smith DR & Zumbo BD. (2003). A prospective study of running injuries: the Vancouver Sun Run “In Training” clinics. Br J Sports Med 37, 239-244.
van Gent RN, Siem D, van Middelkoop M, van Os AG, Bierma-Zeinstra SM & Koes BW. (2007). Incidence and determinants of lower extremity running injuries in long distance runners: a systematic review. Br J Sports Med 41, 469-480; discussion 480.