The Knee Drive is a great exercise for runners as your muscles are used in a similar way to when you are running. This exercise increases your muscular endurance and begins to work your cardiovascular system due to the short sharp nature of the movement. The element of balancing on one leg also benefits your core strength and will pay dividends in your running stability.
To start your knee drive set yourself up in a long lunge position with both feet parallel, facing forwards. Hold your arms above your head. Drive your back knee forwards so that it comes together with your front knee, maintaining a low position. Whilst moving your leg, bring your arms down so that your hands touch your knee at the bottom of the movement before you return back to the starting position. This is a short and sharp movement performed with power.
In order to maintain balance whilst moving quickly on one leg you will need to engage your core.