Very Heavy Sled Pulls For Faster Sprints

Pulling a weighted sled can help improve running acceleration, which is a competitive advantage in many sports. Previous research has tested sled loads between 12% and 43% of body weight. A study recently published in the International Journal of Sports Physiology and Performance used a load equivalent to 80% of body weight.
 
During an 8-week intervention, 16 male soccer players did ten 20-meter sprints pulling 80% of their body weight on a tethered sled. Some ran their sprints with no resistance. After the 16 sessions were completed, timed sprints showed moderate to small improvements in 5 and 20 meter performance for the weighted sled group. Sprint training without pulling a sled produced only small to trivial improvements in sprint performance.