will be replenished. Then hone that work by reducing total volume to boost muscle glycogen levels and immune function. But keep the intensity high in a few key sessions to recruit fast-twitch muscle fibres and to stay sharp physically and mentally. With this mix, you

Runners usually talk about muscles in terms of quads, glutes and hamstrings. Exercise physiologists, on the other hand, talk about muscles in terms of fast-twitch and slow-twitch fibres - which is one of the reasons why physiologists aren't invited

will become proficient at running long, slow miles. My ultramarathoner friends often go on four- and five-hour slow runs, which prepare them for 50-mile-plus races but do little for their ability to smoke a fast 5K.Rule #5 Let your body adapt to increased

sessions every two to four weeks. Generally, these workouts are done at 3,000m pace (eight to 12 seconds per mile faster than 5K race pace). The pace is fast, so don't make these your first repeats of the season. Classic Six to eight lots of three minutes

Sunday. Do what feels right.Saturday: 30-minute run followed by 4 x 100m strides After running easy for 30 minutes, do four 100m strides at your projected 5K race pace to simulate a strong finishing kick. The speed will wake up your fast-twitch muscle