How to Improve Acceleration Part 2

This is part 2 of a multi-part series.  Part 1, which discussed hip mechanics, can be found here.

This part will discuss:

1. which foot is the power leg
2. resistance running with weighted sleds
3. resistance running with isorobic ropes
4. resistance running with uphill running
5. resistance running with parachutes

Without getting into too much detail on how to use starting blocks (which has been covered in detail on this Blog), the first step in improving acceleration is literally the very first step… literally!

It doesn’t matter if it’s from starting blocks, crouch start for 800 meters, American football, Soccer (or football around the world), or even a baseball outfielder.

In short, what you want to do is generate the maximum force from inertia (standing still or motionless) to acceleration to achieve a maximum velocity.  (let’s leave out shin angles for this discussion, please)

Contrary to some High School Track coaches, the power leg should be front leg, not back.

This is especially true in track with starting blocks.

Some may say it’s the instinctive reflex that matters, and that’s why you will see silly drills where you push your blindfolded teammate from behind while standing.  The best way to determine your power leg is ask your athlete to do a 3 step layup with a basketball.  (of course, if they play some basketball and know what is a lay-up!)

Resistance Running

Now that we got that step out of the way…

The best way to practice starts and acceleration is to do starts and acceleration.

But there may come a time for advanced athletes to up the ante, so to speak.  And that involves adding a little extra resistance.

Isorobic Ropes and Sleds

I’ll have to go into high school physics to explain the differences between the isorobic rope and weight sleds, because the work loads are different.  The sleds are moving with the athlete.  The rope provides a more constant resistance, whereas the sled decreases with increasing speeds.

But the good old fashioned isorobic exerciser is great for indoors when you can attach the rope to a wall.  Outdoors require a teammate.  I would avoid temporary anchors as these may come loose and injure someone.  So please make sure it is securely fastened.

Here are some tips and advice for using sleds and isorobic ropes:

1. install the device about half a meter from the ground (18 inches)
2. use distances anywhere from 10-30m (great for indoor workouts)
3. a "slowdown" of 5-10% in expected.  Greater than that usually results in technique deteriorating.  And that is bad.
4. ideally to be used on the track with spikes. 
5. have the belt secured just above the hips no higher than the waist
6. keep proper care not to obstruct the runner with the incoming rope!

There are hundreds of studies out there that demonstrates the effectiveness of sleds.  I’ve included two snippets below, but basically it’s saying (from these studies) that sleds are great to improve acceleration, but showed no improvement in top end speed.  (This statement can be confusing as improving acceleration by means with a longer and more efficient acceleration will improve top end speed and result in a faster 100 meter time).  They also say keep the loads light as more is not often better.

The Greek Study:

CONCLUSION: Sprint training with 5 kg sled pulling for 8 weeks improves acceleration performance (0(-2)0), while un-resisted sprint training improves performance in maximum speed phase (20-40) in non-elite athletes. It appears that each phase of sprint run demands a specific training approach.

The Australian Study:

CONCLUSION: Weighted sled towing is a common resisted sprint training technique even though relatively little is known about the effects that such practice has on sprint kinematics. The purpose of this study was to explore the effects of sled towing on acceleration sprint kinematics in field-sport athletes. Twenty men completed a series of sprints without resistance and with loads equating to 12.6 and 32.2% of body mass. Stride length was significantly reduced by approximately 10 and approximately 24% for each load, respectively. Stride frequency also decreased, but not to the extent of stride length. In addition, sled towing increased ground contact time, trunk lean, and hip flexion. Upper-body results showed an increase in shoulder range of motion with added resistance. The heavier load generally resulted in a greater disruption to normal acceleration kinematics compared with the lighter load. The lighter load is likely best for use in a training program.

Hill Training

I love hills, as long you live in an area that has hills.  A few key points to consider:

1. If you are short on time, then you could skip the weight room as the hills adds an extra "power component" to the training session.  We would do hills in freezing December (in Canada!) so athletes would only need to spend 1.5 hours at track practice to get back home and study for their final exams.  Moreover, the weight room was closed as the gymnasium floor was used for the final exams!  Double whammy!
2. The slight uphill grade keeps their technique in balance, which is "staying tall" and preventing the hips from collapsing.  Also, the ground rises to make contact with the feet, so athletes do not over-stride, which may be beneficial to injury-prone athletes with hamstring problems.
3. The over distance work is a refreshing way to get the special endurance sessions without getting flat or stale from the track, or when the track is closed!
4. You can do hills on a variety of surfaces, to reduce the wear and tear on the track with spikes.

Parachutes

I’m not a big fan of parachutes or “chutes”, so I am purposely leaving it out of this discussion.  I know a lot of SPARQ guys swear by them, but I prefer to have a known finite load number in using sleds.  That’s just me being picky.

Part 3 to be continued…