What is the Longest Distance that a Sprinter Can Run without Overtraining? Fast and Slow Twitch Muscle Fibres!
To Twitch or not to Twitch
Opinion varies on how far a sprinter should run during training; some sprinters train cross country in the off-season to build endurance, but many feel (including myself) that doing so would have a negative impact on their sprinting performance.
Keep in mind that there are two main kinds of muscle fibre – fast twitch and slow twitch.
Sprinters primarily build strength and stamina in their fast twitch muscle fibres, while long distance runners build strength and stamina in their slow twitch muscle fibres.
If you run for more than approximately 15 minutes, your muscles will begin the switch from using primarily fast twitch muscle fibres to using primarily slow twitch muscle fibres. This means the sprinter is no longer training his or her primary muscle fibres.
Alarmingly, there is another consideration: there are two kinds of fast twitch muscle fibre, and one of those kinds will convert to, or turn into, slow twitch muscle fibres if you put enough long distance training in.
The Rest of Running
So, if you are a sprinter, and you don’t want to over train, you should generally not run for more than 10 or 12 minutes at a time, and you should give yourself time to recover completely between runs.
Recovery time between runs is important; if you do not allow yourself enough rest, then your body will react as if you were running long distance, and once again development of slow twitch muscle fibres will take precedence over fast twitch muscle fibres.
This is not to say that a sprinter should never, ever run any longer than 12 minutes … but certainly he or she should not regularly train over such times.
If you are a runner, a coach, or other interested party, please use the comment section below to share your experiences and opinions.