How weight-bearing exercise is better

15 girls

I would like to exercise long-distance running is endurance explosive power and speed! ! (Every day run that)

content will not be much sum up the day up to 10 laps (1 lap 400)

want to buy sand bags tied to the leg workout you down? ? ?

How exercise is better? ? What type? ?

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sandbags tied to the leg exercise endurance in training.

50 meters Accelerative Running 5 times, and just do a few group

sandbags tied to leg line