My first experience running a 5K came on a hot and humid day in New Jersey in early September, 1987. As I ran through the woods in my first high school cross country race, 5 kilometres seemed a long way to run at the time, given my short history in the sport as a sprinter. I soon realized that having speed wasn’t enough to run a 5K; I also needed endurance. That’s one of the things that makes the 5K so appealing—it requires a good mix of endurance and speed.
The 5K has become one of the most common race distances. It’s a good starting point for beginners who want to run their first race and for veteran runners who want to test their fitness. Whether you want to complete your first 5K or run it faster, here’s how to do it.
Whether you’re a beginner or intermediate runner, your weekly running volume is the most important part of your 5K training. That’s because running lots of kilometres stimulates many physiological adaptations to improve your endurance. For example, it improves your blood’s ability to transport oxygen, increases the size of your heart so it pumps more blood with each beat, stimulates the storage of more fuel in the muscles, builds more capillaries around your muscle fibers that bring oxygen-rich blood to them, and increases the number of mitochondria that use oxygen to supply your muscles with energy.
Increase your volume by not more than 2 kilometres per day per week to avoid injury. For example, if you currently run 32 kilometres in four days per week, run no more than 40 kilometres the next week by adding two kilometres to each of the four days. Do not run 40 kilometres the next week by adding all eight kilometres to only one day of running. Run the same volume for 3 to 4 weeks, then back off your volume by about a third for one recovery week before increasing it. When you begin to include speedwork in your week, either drop the overall volume for the week or maintain the volume from where it was prior to adding speedwork. Never add more kilometres to the week at the same time as introducing speedwork.
As a coach, the biggest mistake I’ve noticed runners make is running too fast on their easy days. Since many of the physiological adaptations noted above are more sensitive to the volume rather than the intensity of effort, the speed of your easy runs is not as important as their duration. Your breathing should be controlled and you should be able to speak in full sentences.
LACTATE THRESHOLD RUNS
Your lactate threshold is an important physiological marker that indicates the fastest pace you can sustain aerobically without fatigue. The faster your lactate threshold pace is, the faster the pace you’ll be able to hold for a 5K. Add lactate threshold workouts after you have completed a number of weeks of increasing running volume with easy runs.
Lactate threshold pace is about 6 to 9 seconds per kilometre slower than 5K race pace (or about 10K race pace) for runners slower than about 25 minutes for 5K (about 80-85% maximum heart rate). For intermediate runners, the pace is about 12 to 15 seconds per kilometre slower than 5K race pace (or about 6-9 seconds per kilometre slower than 10K race pace; 85-90% maximum heart rate). Subjectively, these runs should feel comfortably hard. You should just be able to notice your breathing and be able to speak about one sentence at a time.