This all because I am reading an excellent book (The Omnivore's Dilemma by Michael Pollan) which investigates our attitude to food. It is wonderful in the way it investigates different methods of food production and how we relate to them, all the time asking questions about why and how we eat the way we do. The central premise is that being an omnivore is a tremendous evolutionary advantage because the species can live in all corners of earth and survive disasters that might affect any one source of food. However the corollary is that the relationship to other species of plants and animals is complicated because there are always decisions about whether something is safe to eat or how to get the full range of nutrients. Up to now we have relied on traditional cuisine to tell us how we should eat but in western countries (particularly America and UK) that relationship has broken down. We eat from a whole range of cultures without necessarily knowing how the elements are combined, and the way the agriculture, food processing, and distribution industries are set-up exert their own pressures on consumption. It has led to obvious problems of obesity and increasing anxiety about what we eat.
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This is contrasted in the next section with a pastoral idyll, an organic, sustainable, grass-based farm that only sells its produce locally and is so transparent it allows visitors to see everything, even the way it kill their chickens.
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The heart of the farm is grass and the cattle are continually moved to different areas, in strict rotation, by means of mobile electric fences, so that they cut back the grass enough to stimulate further growth and improve its quality. Three days after the cattle have left a pasture chickens are brought in. They eat the fly larvae in the manure and sanitise the field, also they spread that manure and of course their own droppings are very high in nitrogen and there is no need for extra fertiliser. Trees are important in the way that they retain water, provide shelter, alter the micro-climate, provide chippings and biodiversity of the forest helps protect the farm from predators by providing other prey. Everything is related.
(If you want to listen to Joe Salatin, the farmer, the BBC made a Food Programme about him in 2006, which is still available.)
So onto the running bit.
Agricultural has no connection with running but I did wonder if there was any analogy between the differing virtues of monoculture and diversity and ways of training.
There is no doubt about the specificity of training. The way to improve your running is to run; other exercises use different muscles. You can tell this if you have a gap, say for an injury, but maintain aerobic fitness with other exercises, when you start running again it is all a bit hard. There is thus a philosophy of training that just emphasises churning out the miles. The equivalent of monoculture.
Monoculture produces the highest yields per acre and might well be the best way for a number of people to improve their times. Up to a point there is a direct correlation between the miles run and performance. However I wonder if it is necessarily the best route for overall fitness. Firstly, and most obviously it concentrates on a particular group of muscles and a limited range of movements, whilst he body needs so much more flexibility and strength. Secondly, and perhaps related, a highly repetitious load carries the risk of injury.
I am convinced that the only way to improve your running is to be consistent and the only way to achieve consistency is being uninjured. Avoiding injury is therefore an important strategy. If you can do this on high mileage, fine, but we all need to find our limits and the amount we can push yourself before breaking down. If those limits are fairly low then we need other things to compensate; mixing cycling and running for example.
Also lack of strength in other parts of the body can cause problems. We are all now aware of the importance of the core muscles but there are other areas, shoulder for example which also need to be strong. These areas all require work and an increasing amount of work as you age and lose muscle mass. They are best tackled through things like pilates, yoga or resistance training.
If you are mixing running with other things you enjoy it can also help prevent running becoming a chore. The one thing thing that is central to the soft-core manifesto is that running is play, not work; so we must guard against it feeling like a duty.
You can see I am convincing myself of the need for diversity. For some reason I do not like the term cross-training (I could not tell you why, it just sounds wrong in my ear). Instead I like to think of it as integrated training. The ideal being to mesh together activities so that you can run well but be generally strong and fit enough to find maximum enjoyment in your physical exertion, whilst feeling alert for all the other things in your life.
A sort of Polyface running.