Monday, July 22, 2013

Jumping and Weightlifting: Part 2

In Part 1, I laid out why jumping and weightlifting are very much related due to nearly identical mechanics in both the explosion and the landing phases. Because of the biomechanical similarities, I will be discussing the importance of using the Olympic lifts when training jumping athletes in Part 2.

When it comes to athlete's who jump, sprint, accelerate and decelerate, it's a Sports Performance/S&C coach's responsibility to increase rate of force development for their athletes.  There is no better movement in a coach's tool box in terms of developing rate of force development than these lifts.  The second pull of a clean, for example, produces a total average power output of 6,981W.  Conversely, the deadlift, a more absolute strength exercise, only produces a total power output of 1,274W. (1)  If you aren't incorporating these potent movements into your program, you're doing your athletes a huge disservice.

One of the best ways to test power is through a vertical jump test.  Studies suggest that the snatch and C&J are "beneficial in improving power," so in order to improve vertical jump test results and in turn power development, train by performing a "vertical jump with extra load" (i.e. a snatch or clean & jerk)! (2)

Since jumping involves all aspects of the lower extremities in a sequenced event, then movements that "stress the body in a similar fashion, such as the power clean and snatch, hang clean, or plyometrics, should be chosen."(4)  This particular study also suggests that "care should be taken to emphasize the second pull, as this is the portion that most closely replicates the jumping motion." (4)  This point here stresses what was discussed in Part 1 - proper mechanics.  Mechanics are king, and it's something that is a big miss with most coaches who deal with athletes.  Take the time to learn it properly.

If you are using or teaching improper mechanics in the pull of the snatch or clean, (i.e. not readjusting the knees back under the bar in the second pull, bringing your shoulders back too soon, using your back and arms as opposed to your legs, staying back and driving through your heels, etc.), the benefits of force production that these lifts provide are not being maximized.  Again, one of the biggest priorities of training athletes is to maximize their rate of force production and efficiency.

It's also recommended to incorporate the lifts for athletes who need to improve jumping skills because they help with "neural learning of optimal motor unit recruitment patterns for the activity, which is needed for rapid increases in propulsion force magnitudes...rather than simply increases in muscular strength."(3)  Strength only matters so much when you are an athlete.  What truly matters is the ability of an athlete to express strength fast and powerfully.  A 227kg/500lb back squat doesn't mean crap if you can only clean 100kg/220lb.  That's an athlete who either has no ability to generate power, or has no idea what they're doing...or both.

Jumping is a skill in and of itself that is often overlooked because there are many athletes, even at the highest levels of their individual sport, who do not have excellent coordination when it comes to transferring energy from the legs through the body and into the arms.  You have to be coordinated in order to efficiently perform the lifts, and utilizing them as much as you can in training will expedite the development of coordination and kinesthetic awareness in athletes.

It is also the Sports Performance/S&C coach's responsibility to make athletes more durable and minimize the chances of injury.  Most sports injuries don't happen because of acceleration, they happen because of deceleration, or rather poor deceleration.  This is where the impact phases of jumping and weightlifting comes into play.

The impact of a jump, especially when done on one leg or off balanced in a game such as basketball or volleyball, can be very stressful to the muscular system (4), and if not trained to absorb the impact properly, injuries can happen.

A study reported that the knee extensors (quads) were the greatest contributor to lower extremity work in the impact phase of a jump, and in order "to absorb energy in landing activities, strength of the knee extensors is critical." (6) The Olympic lifts, especially the clean, are second to none in developing the strength and flexibility of the lower body in order to absorb the shock of the impact phases of landing, and therefore, should be incorporated in an athlete's program.  Additionally, the study reported that "knee flexion angle was not different between the power clean and jump landing."(6).  This is a big reason why it is crucial to teach athletes a solid catch position, i.e. proper MECHANICS.

In conclusion, the Olympic lifts are king when it comes to developing rate of force development.  Couple that with the nearly identical mechanics of a vertical jump, and you have a potent training tool when integrated into the program of jumping athletes.  The Olympic lifts can also improve an athlete's durability due to the ability to absorb large impact forces.

Ultimately, if proper mechanics aren't taught or used, an athlete won't gain the full benefit these lifts can provide.  It's the responsibility of the coach to gain the knowledge and skill of not only being able to teach the lifts correctly, but first and foremost, being able to do the lifts properly and efficiently themselves.

Now go learn, implement, and coach!



Monday, July 15, 2013

Jumping and Weightlifting: Part 1

There's a lot of discussion out there about the significance, or insignificance for that matter, of jumping and weightlifting.  This will be broken up into a 2 part piece.  In Part 1, I'll explain how jumping is mechanically related to and used in weightlifting. In Part 2, I'll explain the importance of using the lifts as a training tool for training athletes that jump.

Any information and commentary made will be drawn from peer-reviewed research that has been published in scientific research and sports journals.  I've provided the links to these articles for you to read for yourself as well.

First, do we actually jump when weightlifting?  In a way, yes. Now, we're not talking about jumping in the sense of elevating the feet off of the floor as high as we can.  We're talking about jumping in regards to creating the vertical propulsion on the bar, or the "drive" portion of the jump.

Biomechanical studies have shown the second pull and jumping be similar and nearly identical.  One study explained that "the angular displacement of the two movements follows the same time-sequence: from proximal to distal direction, the hip joint muscles are activated first, followed by the knee joint while the ankle is activated last." (1)

While weightlifters's feet don't elevate high off the floor like a vertical jump, the feet elevate just enough for them to quickly reposition laterally in order for the lifter to transition under the bar.  This is largely because of the load on the bar and the ability to coordinate the timing of the hips to retract with speed.  If a person, however, produced the same force into the ground as they would when lifting, they would likely elevate from the ground.  Because of this, the second pull of the lifts is described as a "vertical jump with extra load."(1)

Weightlifters are known to be some of the best jumpers in the world.  One study suggests that this may be attributable to the "high degree of explosiveness (in the sense of mechanical power generated) required for success in the sport, and qualitative and quantitative similarities between the lifting movements and the vertical jump."(2)

Is using the word "jump" a good cue?  That's up to you as a coach.  It must also be made clear, however, that a cue is used to get athletes to do something the coach wants.  A cue does not describe what is mechanically happening.

Some coaches don't like to use "jump" as a cue because jumping forces lifters up on their toes too soon, as well as slows down the transition under the bar.  It should be made clear that jumping does not create this issue necessarily.  It is a mechanical and/or timing issue that is not being done correctly and needs to be addressed. To address coming up on the toes too early, a simple fix is to cue the athlete to keep the foot on the ground longer.

Conversely, you may find that your athlete's can easily relate to the cue "jump" because of their past or current athletic background (i.e. jumping athletes).  Part of a coaches job is to make things relatable to their athletes.  This is one way.

Now that covers the firs phase of the jump.  What about the second part of the jump - the landing?

Jumping and weightlifting also involves impact phases.  Weightlifters and athletes must have the ability to absorb the impact from the ground and from the bar.  One particular study found that "the correspondence in kinematics between impact phases of jumping and weightlifting tasks suggests similar strategies are used to perform both types of activities." It went on to conclude that "weightlifting tasks share similar biomechanics to landing from a jump (specifically at the ankle knee and hip)..."(3)

So to sum things up, to say that we aren't or shouldn't be jumping in weightlifting is wrong.  Research has shown not just in the propulsion phase, but also more recently, in the landing phase, the mechanics of both are essentially the same.  If you took away the video feedback and just had the empirical data to review of both a snatch or clean and a vertical jump, you would be seeing the same data and feedback.

A weightlifter's errors of jumping forward because the heels are coming off the floor too soon or transitioning under the bar too slowly is because of mechanical and timing issues, not "jumping" issues.

When in doubt, just jump!


References:

1) Biomechanical Analysis of Snatch Movement and Vertical Jump: Similarities and Differences

2) Propulsion Forces as a Function of Intensity for Weightlifting and Vertical Jumping

3) Characteristics of Lower Extremity Work During the Impact Phase of Jumping and Weightlifting

Wednesday, July 10, 2013

Specialization at a Young Age?

Are we having young kids "choose" their sport and specialize too soon?  At the age of 12, or younger in some cases, coaches are making the kids, or parents for that matter since they have to foot the bill for these expensive clubs, choose a sport and commit to year round training and competition.

The problem with this is that these kids are neglecting a crucial component of their physical and athletic development.


Research done by Russian sports scientists such as R.A. Roman, S.A. Medveyev, L.N. Sokolov, etc., suggest that before specialization in a sport should occur, youths must be involved in some sort of GPP training (i.e. running, jumping, throwing, gymnastics, etc.).  This might occur between the ages of 8-12 years old. This type of training is crucial for a youth's athletic development because it develops and prepares their joints and ligaments, cardio-vascular system, as well as general athleticism.  This is the base that these kids can build upon when their year round sport training becomes more rigorous.

Once specialization actually starts, around the age of 15 or so, the fundamentals of technique are hammered.  Training load and intensity is still very light and is not increased until one becomes proficient in the sport specific technique.


So what do you set a youth up for athletically if GPP training is neglected?

I came across this article a couple of days ago that addresses this issue in some capacity.  It's about the alarming rate of "adult, mature-type sports injuries" in youth athletes.

Dr. Andrews explained that the two major factors leading to this spike in youth injuries was two fold: specialization and professionalism.  Specialization leads to playing one single sport year round.  Professionalism is taking these young kids and trying "work them as if they are pro athletes, in terms of training and year-round activity."  At this young age, these two factors lead to overuse injuries.  The bodies of these kids haven't been developed enough to handle the training they're going through.

While Dr. Andrews doesn't address GPP training, GPP before specialization is a better solution to the problem.  Year round sports can be difficult on the body; therefore, the body must be physically prepared and ready to take such a beating.  If the body is not physically ready, injuries will happen.  Moving away from the tried and true philosophy of GPP as a youth and into specialization is becoming detrimental and injurious.  What are you going to let your kids do?