Several studies have now found resisted sprinting to be an effective method for enhancing acceleration.
Many of these studies investigated the impact of loading a sled with anywhere between 5-80% of an athlete's body weight and running as fast as possible over short distances.
What has not received as much scientific scrutiny is walking with loads far exceeding an athlete's body weight for the purpose of speed development.
In practice, this often means stacking a pile of plates on a sled and dragging it at a slower pace:
Years ago, strength coach Joe DeFranco dubbed these "Heavy Ass Sled Drags" (or HASD) and claimed them a key factor in improving his football players' 40-Yard Dashes.
After utilizing them with my athletes, I can confidently say I believe HASD also have great carryover to skating speed for hockey players.
In fact, I think heavy Sled Drags may be one of the best "hockey-specific" off-ice speed training tools out there. I suspect this partly to do with the longer ground contact times observed in skating compared to sprinting. Although ground contact times seen in elite sprinters last less than 0.1 seconds at top speed, the forward skating stride takes a bit over 0.3 seconds.
Furthermore, beyond the initial acceleration phase, sprinting is characterized by a more upright posture and faster turnover of the feet, and it relies more on the stretch reflex. Contrast that with skating, which involves a constant forward lean and a more pronounced "pushing" motion on each stride. This is exactly what occurs in a heavy Sled Drag.
In addition, Sled Drags also directly strengthen the hips and quads, which are responsible for generating lots of force to propel you forward. Several of my players have remarked that their push-off on the ice feels stronger since we began implementing this exercise as part of their off-season training.
For example, Detroit Red Wings draft pick and Boston University junior Kasper Kotkansalo told me last summer that he feels these heavy Sled Drags have really helped his skating, particularly during the transition and top speed phases.
In the video below, Kasper drags a sled weighing over 500 pounds. A few weeks after it was shot, he posted the fastest skating time in preseason testing at BU:
It's one thing when athletes think an activity or drill boosts their performance. But when you can cement that subjective perception with objective proof of success, you know you're on to something.
How to Do Heavy Sled Drags
Heavy Sled Drags are an easy setup. You need three items—a bunch of plates, a sled and something sturdy to attach it to your torso—along with roughly 10-20 meters of uncluttered space.
Follow these basics and you're good to go:
- For attaching the sled, a specialty harness seen in strongman competitions is optimal. But a pull-up/dip belt made of soft material (so it doesn't dig into the skin around your lower abdominals and hips) also works very well.
- The first time you try these, a good starting point is to use an external load equivalent to your own body weight. So, a 200-pound male athlete would pile 200 pounds on the sled. For stronger individuals, this may be fairly light. If that's the case, gradually increase the weight over the following sets until you're towing a challenging resistance.
- You must be able to walk at an even pace. If you have to take breaks to complete a rep, the load is too heavy.
- Precise loading parameters will be impossible to prescribe because each sled will have a different amount of friction depending on the surface (turf, grass, concrete) it's used on.
- If you're so strong that you run out of plates, a teammate (or intern!) can hop on the sled to provide extra resistance.
Recommended reps and distance: 4-8 reps at 10-20 meters. Allow 120-180 seconds of rest between reps.
In addition to being a phenomenal offseason exercise, Heavy Sled Drags are also a good option to include as an in-season strength/speed program.
Since they involve a minimal eccentric component, post-workout muscle soreness won't be an issue. Sled Drags cause minimal nervous system and local muscular fatigue in the lower body. You build the legs and lungs without digging yourself into a recovery hole. Isn't that exactly what we all want when victories and trophies are on the line?
Morin, JB et al. "Very-Heavy Sled Training for Improving Horizontal-Force Output in Soccer Players." International Journal of Sports Physiology and Performance. 2017 Jan; 12(6):840-844.
Taylor, MJD & Beneke, R. "Spring Mass Characteristics of the Fastest Men on Earth." International Journal of Sports Medicine. 2012 Aug; 33(8):667–670.
Robert-Lachaine, X et al. "Impact of hockey skate design on ankle motion and force production." Sports Engineering. 2012 Dec; 15(4):197–206.