Marathon and ultra-distance runners can regularly be found out on the roads at the crack of dawn on weekends, diligently putting in their “time on your feet” as they log the weekly LSD. For them there are no two questions that the weekend long run is a good idea. It is a simple equation, to get fit for running far, you should, run far.
So what about the runner wanting to improve their 5k or 10k time?
What many runners do not realize (because it defies logic) is that the key to cracking that PB is often less short fast running and more long steady running.
When running a 5k, not matter how good you are, you will never be running at your maximum speed (about what you would run over a 40m sprint), even when sprinting for the finish line you are still way below this speed. What you will be running at is the maximum speed that you are able to maintain for the 5k without your legs turning to jelly (also known incurring “Oxygen debt”).
When running at our 5k pace, the main metabolic process used by the body to release energy for the muscles to work, is the are aerobic process, which simply means, the main ingredient is good old Oxygen which we breath in. The greater the oxygen supply, the more energy that can be produced. Oxygen to breath in is in no short supply, however each individual runner, depending on their physical condition, is limited in how much oxygen can be taken up and used by the muscles per minute. The faster the pace, the higher the demand. When demand is higher than supply, “Oxygen debt” is incurred with the accompanying build up of lactic acid resulting in the famous jelly legs.
The key then to running faster, is to increase the oxygen supply and uptake in the muscles. This is done through long steady state running. The following adaptations take place, the capillary beds (which transport oxygen) in the muscles are expanded and new ones are created, the heart muscle becomes bigger and stronger so it is able to pump more oxygen rich blood with each stroke, your lungs become more efficient and blood circulation in general improves throughout the body.
What are the nuts and bolts of these runs?
The best pace to do these runs is at about 70% of your 5k pace. It is a pace which is comfortable enough to talk, but still fast enough to leave you feeling pleasantly tired at the end. The runs can vary in length from 1 hour to 2 hours and can be done up to 3 times a week. Try do at least one a week of 90-120 minutes. Just remember to start by doing no more than 10% of what you are currently doing and to build up slowly.
Train hard and remember to enjoy the journey!