Of course, during the basic period we don`t use repetitions very fast. We prefer to work for improving all the types of SPECIAL RESISTANCES, expecially STRENGTH ENDURANCE that has a very big influence on the Specific Endurance.
For example, using circuits lasting about 3/4 min with very long recovery, at the max. intensity, we can increase the periferal endurance imrpoving at the same time strength and capyllarization. An example of circuit can be the following :
- 80m bounding (flat)
- 10 squat jumps on the place
- 300m running very fast on flat ground (finishing where a hill starts)
- 10 exercises for abdominals starting with the back on the ground
- 60m sprinting climbing
- 40m skipping very fast climbing
- 60m sprinting climbing
- 40m bounding climbing
- 60m sprinting climbing
- 10 squat jumps on the place again
- 200m very fast climbing
This circuit uses about 400m flat plus 360m climbing, and is very good for middle and long distance. With athletes of 800m, we can use the same type of work with shorter distances, lasting no more than 2 min.
Because the only way that we use for recruiting the most part of the fibres of one muscle is WORKING AROUND THE MAX INTENSITY, and the capacity of recruiting fibres is very important not only for the speed, but also for the endurance, due to the turn-over of the fibres of the same muscle, every circuit must be done at max intensity. At the end, the level of lactate is very high, and we have to recovery well before going for another circuit (normally, 5/6 min for long runners, 8/10 min for 800m runners).
But, what is important to know, is that, after using repetitions on track at high intensity (for example, 4 x 600m at 1:22 rec. 6/8 min for an athlete able running 1:47) without adequate aerobic support, for a time longer than 3 weeks, you can check that your Threshold decreased. Instead, after using circuits with adequate aerobic support, your Threshold increases. I suppose that this fact is due to the more global involvement of a higher percentage of fibres during the training, having a combined effect with the aerobic work able to push the Threshold, while fast tests on track have an OPPOSITE effect on the Threshold.
I hope that readers can understand my post, because it is for me very difficult to explain without dictionary a scientific concept. So, may be that I wrote some word that does`nt exist. I apologyze, hoping that someone of mother tongue can translate in good English my words.