Although one-kilometre repeats can be the best judgement of where you are in your 5K training, running them over and over again can get boring. There are several ways you can add a little zing to your repeats by breaking up the interval or changing the speed.
An Air Up There Run Crew workout. Photo: Josh Tenn-Yuk
The broken kilometre workout is designed to get you more comfortable and confident with your goal 5K pace and improve your lactate threshold.
When running at a fast pace, your muscles use lactate as a source of energy. The longer and faster you run, the more lactate your muscles produce and use. The goal of interval training is to build up your lactate threshold, so it can be cleared as quickly as it is produced. Having a higher lactate threshold can help your muscles work efficiently at a faster pace.
The broken kilometre workout alternates between 600 and 400 metres at 5K race pace, separated by a short rest between intervals and a slightly longer rest between sets.
A University of Toronto track workout in 2019. Photo: Maxine Gravina
Six sets of 600m/400m with 200m jog rest between reps and two minutes slow jog rest between sets
There are two or three ways to do this workout. Firstly, it can be done on an athletics track to precisely measure the distance and your rest. Another way of doing this workout is by finding a 1,200m loop and setting markers along the way.
If you do not have access to a track or a 1,200m loop, make modifications and do six reps of three minutes/90 seconds with one-minute jog rest between reps and two minutes jog rest between sets.
The pace of each rep should be done at your goal 5K pace or slightly faster. If your goal is to break 20:00 minutes, do the reps at 3:55 to 3:58/km. The short active rest between reps will develop your lactate threshold, preparing your muscles for race day.