Maximal Force Production for Reducing Injuries

Injuries occur in all sports. Unlike ground-based sports, nearly all swimming injuries stem from overuse. These overuse injuries commonly occur when an athlete is unable to respond during a fatigued state. During this state, the body does not respond appropriately to an unexpected stimulus.

This ability to react to an unexpected movement is dependent on many variables. One variable infrequently mentioned is spinal motor control/neural drive. This control is potentially moderated by the sympathetic nervous system (fight or flight) system and studies suggest spinal motor control/neural drive is higher in men and power trained athletes (Johnson 2012).

Spinal motor control/neural drive may also contribute to swimming success, as a recent study found a correlation between handgrip strength and 100-meter freestyle performance. Many will doubt the correlation between handgrip to predict 100-meter freestyle performance, but handgrip strength may utilize spinal motor control for a maximal contraction (Autonomic Nervous System Readiness; Handgrip Strength Predicts 100-meter Performance?). However, more research is required on this topic, assessing a broader and diverse population. Keep in mind, handgrip strength is believed to inversely correlate with overtraining. This suggests these 100-meter freestyle swimmers could have just been more rested than their peers.

One potential mechanism for improving spinal motor control/neural drive is through resistance training, as the results of a current study imply strength and endurance training result in different neural response. However, future studies must assess the response in trained athletes, before a true correlation before one can draw the conclusion that the resistance training was responsible for improvement. Moreover, the correlations with the neural adaptations are essential criteria for recommendation for the swimming community. Neural drive may also differ in a population of simultaneous resistance and endurance training (ie swimming). However, neural drive may be the avenue for improvement from resistance training in swimming (Vila-Chã 2012).


One example of this training is the rack pull:

Another area to consider is a more power training approach to dry-land after a proper foundation of training (general strengthening and injury prevention) is achieved. However, this approach must not increase the risk of injury (I suggest shortened range of motion movements), perform excessive repetitions (interferes with the principle of specificity), or result in excessive soreness (impairing motor programming).

This doesn't suggest strength training is a requirement for all swimmers, but does suggest an explanation of the consistent use of resistance training in elite swimmers. Lastly, keep in mind, resistance training (especially supra-maximal power training in shortened range of motion) must only be implemented once the swimmer has demonstrated that they have the muscle stability and timing necessary to perform the training in a safe manner, as the top priority of any dry-land program is keeping the athletes healthy, for high-intensity swimming training.

Reference:

  1. Johnson ST, Kipp K, Hoffman MA. Spinal motor control differences between the sexes. Eur J Appl Physiol. 2012 Mar 8. [Epub ahead of print]
  2. Vila-Chã C, Falla D, Correia MV, Farina D.Changes in H reflex and V wave following short-term endurance and strength training. J Appl Physiol. 2012 Jan;112(1):54-63. Epub 2011 Oct 13.

By G. John Mullen founder of the Center of Optimal Restoration, head strength coach at Santa Clara Swim Club, creator of the Swimmer's Shoulder System, and chief editor of the Swimming Science Research Review.

Plyometrics and Swimming

We’ve covered plyometrics for swimmers several times on this site, but it’s a topic worth revisiting as many teams are in the early season, and ready to install new programming if they haven’t already done so.  With images of Ryan Lochte’s epic training routines shown across the globe during the Olympics, it’s natural that more want to copy the world’s best (but keep in mind Lochte is a former varsity basketball player with some natural “hops”…)

A common belief is that plyometrics aid starts and turns in swimming.  Multiple studies have shown that plyometrics may improve block starts (Bishop 2009, Potdevin 2011).  However, plyometrics aren’t the only way to improve starts and may adversely affect in-pool training, so we must keep all results in context.  It makes logical sense that plyometrics would improve turns, but so far the evidence on both sides has been limited.  Cossor 1999 found no effect of plyos compared to in-water training, but that study was with youth swimmers training 3x per week. 

With sound evidence that plyometrics may help swimming, the real challenge is blending it into a training program safely and effectively.   Traditionally thinking has required a 2x body weight squat before using lower body plyometrics.  But with looser definitions of plyometrics now in vogue, that requirement is probably too restrictive.  For example, old-school kinesiology aficionados might exclude skipping and bounding from the definitions.  However, modern lexicon has expanded to include locomotive skills like bounding, hopping, skipping, and jump rope as plyometrics.   An expanded definition doesn’t mean people with crappy squats get to do four foot depth drops, but you need not squat huge numbers just to skip across a grass field. 




The choice to include plyometrics for swimmers in a dryland program can include four considerations…

1)  Swimmer – What limitations and attributes does the swimmer bring?  Do they have any prior injuries?  Any current injuries (often surprising how many ignore that one…)?  Proper mechanics in basic lifts and movement patterns are crucial prerequisites at any age.   Do they have any experience as a land athlete or any prior dryland training?  Sprinter or distance?

2)  Choice of exercise – What asked to describe “plyometric training” one person may think jump rope or unstructured playtime, while another may think repeated depth drops and squat jumps.  Maybe it’s cool to say “our team does plyos” but it’s important to find the most appropriate ones. 

Height off the ground, weight of the individual (along with external resistance), and volume of reps are all factors to consider with each exercise.  These all operate on a continuum.  You can do high reps if your plyometrics is jumping rope.  If you’re doing four foot depth drops, probably lower reps are in order, with room for adjustment in the middle of the continuum.

Despite these risks, plyometrics also be valuable for rehabilitation, particularly with the upper body.  Swanik (2002) found that an upper body plyometric program throwing medicine balls against a trampoline resulted in improved proprioception and kinesthesia compared to a control group doing only resistance training.  Still, a shoulder stability foundation is necessary before undertaking such a program.

3)  Training plan – It’s one thing to program plyometrics for a third string wide receiver who rides the bench or a recreational gym goer for whom the plyometrics are the most exhaustive thing they’ll do each week.  It’s quite different to demand high load and high skilled moves for swimmers before or after three hour practices in the middle of twenty hour training weeks (many of whom are clumsy on land to begin with).   No matter how great plyometrics may be, ask carefully whether a high skill and high load dryland move fits into the swimming plan at that moment.

4)  Environment – It’s awfully grating to see coaches having swimmers (or any athletes/clients) perform difficult plyometrics with poor footwear on inappropriate surfaces like stadium bleachers and concrete.  Obviously not everyone has a perfect soft turf field to perform their exercises, but rarely does the benefit of any dryland training justify increasing injury risk by neglecting basic safety protocol.  Remember, most injuries occur when you meet the ground, not when you are going up!

Conclusion

Plyometrics are a potential asset to any dryland program.  Always consider the swimmer, exercise, training plan, and environment to make informed choices on how to fit them into your training.

References

  1. Potdevin FJAlberty MEChevutschi APelayo PSidney MC.  Effects of a 6-week plyometric training program on performances in pubescent swimmers.  J Strength Cond Res. 2011 Jan;25(1):80-6.
  2. Bishop DC, Smith RJ, Smith MF, Rigby HE Effect of plyometric training on swimming block start performance in adolescents. J Strength Cond Res. 2009 Oct;23(7):2137-4. 
  3. Cossor JMBlanksby BAElliott BC.  The influence of plyometric training on the freestyle tumble turn. J Sci Med Sport. 1999 Jun;2(2):106-16.
  4. Swanik KA, Lephart SM, Swanik CB, Lephart SP, Stone DA, Fu FH. The effects of shoulder plyometric training on proprioception and selected muscle performance characteristics. J Shoulder Elbow Surg. 2002 Nov-Dec;11(6):579-86.
By Allan Phillips. Allan and his wife Katherine are heavily involved in the strength and conditioning community, for more information refer to Pike Athletics.