Resisted Sprint Training: Parachutes vs. Sleds vs. Incline Running
Linear speed training is a hot topic in all sports. After all, no matter what sport you play it is beneficial to be fast. As simple of a movement as running is, there are many factors within it that must be taken into account. This is referred to as the kinematics of running. These kinematics include measures of stride length, stride frequency, range of motion measurements at each joint, and ground contact time to name a few. To keep from getting too scientific I will give you my thoughts on three types of resisted sprint drills in terms of their benefits and drawbacks for athletes using them.
There a three very popular types of resistance drills: Parachute sprints, sled sprints, and hill/incline sprints. Studies have shown that all of these drills benefit athletes by increasing their acceleration rate, but from an application stand point how do these tools measure up? As a semi-professional track athlete for four years and now a track coach going on six years I have had the opportunity to use all of these implements personally, and coach using these implements as well.
First, from a few research articles…
[1] One study took experienced athletes and trained them 3 times per week for 4 weeks with a large parachute and spikes shoes doing 50 meter sprints. After 4 weeks, the resisted sprint group improved their 0-20 meter speed by 3.3% compared to the unresisted group who improved by 1.8%.
[2] The next study compared inclined treadmill and ground resistance training (sled resisted). The inclined resisted group increased their speed from 0-9.1 meters by 5.4%, compared to the ground resisted group who increased their 0-9.1 meter velocity by 2.9%.
[3] A study examined 8 weeks of 2x/wk training of light sled (around 13% of body mass) towing versus heavy sled (around 43% of body mass) towing on 10 meter acceleration times. The heavier sled towing group significantly decreased their 5 meter acceleration by 5.7% and the 10 meter acceleration by 5%, whereas the lighter sled towing group only increased 5 meter acceleration by 2.8% and 10 meter acceleration by 3%.
Now for the application…
As I said, I have used each of these implements many times in the past. I have had positive and negative experiences with each of them. Over the years I have found the implements that have brought me the most success, both for myself and my athletes.
Parachute Resisted Training
Parachute resisted sprinting was one of the most popular forms of resisted sprint training in the early 2000’s. This tool was very popular for two main reasons. First, the parachute’s aesthetic effect. There was nothing cooler than watching your favorite NFL player sprint down the field towing a giant parachute behind him then going to practice and doing the same thing yourself. The second big reason for their popularity was the accessibility. These implements could be easily placed in a bag and carried anywhere you went. You could also pull them out and use them in any location where you had 40-70 meters to run. This seems like a perfect tool, right?
For all its positive traits, the parachute has a few glaring negatives as well. The biggest issue with the parachutes can be getting them to inflate completely. Too many times I have seen athletes take off into their acceleration to find that it took the parachute the first 10-20 meters to inflate. By that time the athlete was out of their acceleration phase. This is very counter productive considering the parachute has the greatest effect on the acceleration phase and not the top end speed portion of the sprint. The second issue that would commonly arise would be the lack of ability to adjust the parachute for the athlete. If you have only one or two parachutes of the same size and you training athletes of different ages and strength levels then you will inevitably have a younger athlete who struggles and fights against the resistance of a parachute that is too large for them, causing the biomechanics to be altered in a negative way, or on the flip side you will have an older, stronger athlete dominating the parachute without a way to increase the resistance unless you have a second parachute or a fortunate gust of wind comes along.
Sled Resisted Training
The second form of resistance training is sled resisted sprinting. These implements are becoming more popular at all areas of athletics. If you follow any training facilities on Instagram you will likely see a weighted sled used in a myriad of exercises with all levels of athletes. This tool, like the parachute, has a great amount of aesthetic and audible appeal to it for athletes. This is the image of an athlete overcoming the forces of a massive steel object at high power outputs to show his/her prowess over that piece of metal. With all the hype surrounding sled-resistance, is it the top tool for athlete development?
To be honest, the sled is one of my favorite training tools. Yet, I am still the first to acknowledge its downfalls.
First, the sled is great for providing a constant backward force throughout the exercise unlike the parachute which can change magnitude based on wind speed and direction. The sled allows for the user to load it to the level that is sufficient for power development without detriment to kinematics. To this point, I am sure many of you have heard of the 10% rule when it comes to loading the sled. I understand where the originator of this rule was coming from in regards to maintaining kinematic awareness, however I will adjust my sled weight based on the athlete’s performance within the sessions training. If the athlete is fully recovered and prepared for training, I will likely load the sled heavier than normal in order to increase the training stimulus. However, if the athlete is tired, sore, had a long day in school, or is being effected by some other external stressor then the load will be decreased? I have no mathematical formula. I simply use my eyes and observe. If I believe that the load is effecting the athlete’s mechanics in a negative manner then the weight will be decreased. If I believe the athlete is excelling at the current weight and could handle more then I will increase the weight at that point. As you seen in the third cited study above, heavier sled sprints created a more positive outcome than lighter weights did. Ideally, I will keep the sled weight between 15% and 30% of the athlete’s body weight.
One other reason that I like the sled resisted sprint is the directional force of the pull by the sled. When a parachute inflates it typically rises over head which causes a backward and upward directional force. If this occurs within the acceleration then it could pull the athlete out of his/her acceleration prematurely. Since the sled pulls backward and down it does not have this upward pulling effect. I can also adjust the point of force on the body by switching between a belt and a shoulder harness to attach the athlete to the sled. I commonly use a shoulder harness, for the reason that many athletes already have an issue achieving full extension at the hip when accelerating. By adding the weight belt you are introducing yet another force for them to overcome in order to achieve full extension.
Now for the drawbacks of the sled. Accessibility. The biggest issue I have with the sled is its limitations regarding transportation. If you train in multiple locations as I do and you don’t have sleds and weights at each location then you will be constantly loading and unloading multiple sleds and weights for each training session. If you do this two or even three times a day, you will be ready to turn back to the parachutes.
Hill/Incline Sprints
The final tool that I see commonly used in acceleration training is incline training. I have seen, and experienced it both on hills and on high speed treadmills.
The incline sprint drills are great drills for both increasing vertical force displacement and also improving mechanics. Nick Winkelman has done a great deal of research regarding external cues and their use within training. Last fall I listened to him speak at the University of South Alabama regarding acceleration training and part of this talk incorporated external cueing. This technique refers to using the external factors of a training session to elicit results instead of the coaching providing all of the cues throughout the session. One example that he used was inclined running. He explained that by having an athlete sprint up a hill they instinctually drop into a 45 degree angle, increase their hip and knee flexion, and gain full extension in the lower limb joints when applying force into the ground. By using this drill you have decreased the amount of coaching needed and taught the athlete how to find this position. When using an incline for training purposes, I try to place athletes on an incline anywhere from 5-30 degrees depending on the athlete’s level of strength.
With the opportunities that a hill training session allow the major drawback is quite apparent. It is very hard to find the ideal hill and you have to base your training around it. By this I mean you must train when the weather is nice, and it must not be in use by other groups. Some groups have substituted a hill for high speed treadmills with the ability to reach excessive inclines. While I have used these in the past and understand their appeal, my greatest issue with these is the fact that the velocity is created by the treadmill. The athlete is not producing the force to make the treadmill run. In my opinion, this is an exercise in overspeed training in which the athlete is forced to keep up with the treadmill instead of determine their own velocity.
At the end of the day if your biggest decision is to decide between the three of the tools above, then half the battle is already won. You have made a giant step in the right direction by just incorporating some type of resisted sprinting. Choose the option that is best for you based on the tools allotted to you and the time you have to spend in these areas. As always, coach smarter, not harder.
1.The Effects of Resistance Training Using Parachutes on Sprint Performance. KLIMENTINI MARTINOPOULOU, POLYXENI ARGEITAKI, GEORGIOS PARADISIS, CHRISTOS KATSIKAS, ATHANASIA SMIRNIOTOU. http://www.biologyofexercise.com/712.pdf
2.Predictors of Sprint Start Speed: The Effects of Resistance Ground-Based vs. Inclined Treadmill Training. GREGORY D. MYER, KEVIN R FORD, JENSEN L BRENT, JON G DIVINE, TIMOTHY E HEWITT. http://www.accelerationqc.com/wp-content/uploads/ground-based-vs.-inclined-treadmill.pdf
3.The Effects of Weighted Sled Towing With Heavy Versus Light Load on Sprint Acceleration. KAWAMORI N, NEWTON RU, HORI N, NASAKA K. Journal of Strength Conditioning Res. 2014 Oct 28(10):2738-45. doi: 10.1519/JSC.0b013e3182915ed4.