Building the Jack-of-All-Traits Legs Workout With Squats, Jump Squats and Body Weight Plyometrics? At Least for Physical Education Students that Seems to Work.

Image 1 (musclemag.com): You don't have to restrict your plyometrics to leg exercises - plyometric push ups, for example can help you to build a bigger chest and a bigger bench.
"How many sets, how many reps, which exercises...?" These are the standard topics people are chatting about at the gym. Things like ROM (range of motion), explosive training or plyometrics, on the other hand, are almost as rarely talked about as they are done.

What about you? When was the last time you counted the seconds it took you to compile the concentric phase of a squat? What about "plyos" (=plyometric exercises) do you have some in your current routine? No? According to the results of a recently published study by Eduardo Sáez de Villarreal and his Spanish co-workers, this may be a mistake - at least if your goal is not solely to maximize muscle size, but also muscle function.

Plateau busting plyometrics and power building explosives - more than just hilarious bogus?

In a randomized trial, 60 active male physical education students (78.3kg body weight; 12.7% body fat; 20.4y mean age) were randomly assigned to one out of five training groups. For the subsequent 7 weeks the students performed one of the following exercise regimen (see A-E in table 1) three times per week for a total of 21 sessions (participants were instructed to avoid any strenuous physical activity and to maintain their usual dietary habits for the duration of the study).
Table 1: Training program for all the groups, participants were randomized to groups and trained 3x/week for 7 consecutive weeks; velocities are given in m/s for the concentric phases of the full squat equaling 1 m/s = 60% 1RM, 0.9 m/s = 67%, 0.8 m/s = 74%, 0.7 m/s = 80%, 0.6 m/s = 86%; full-squat means thighs to the ground, while squats are done until 60°;
plyometric jumps are done with body weight only (based on Sáez de Villarreal. 2012)
While the subjects in group A performed all types of training within one session, the other three groups served as what you may call a "control" the former "crockpot" regimen was compared to. Thus the researchers expected to be able to decide
Video 1 (click to watch): Loaded countermove- ment jumps (CMJLoaded)
  1. whether the combination training (A) would elicit similar performance increases as a specialized training routine and
  2. which of the specialized training routines (B-E) would elicit the greatest effects on the two outcome variables of the study.
The latter, i.e. total strength and explosiveness, as well as the 30m sprint performance of all participants were assessed in individual tests at baseline and at the end of the 7-week period and the results did in fact partially confirm what conventional wisdom would tell us: Training for speed will make you faster, training for strength will make you stronger *surprise!*

30m sprint improvements: C > A > B > D > E - but all below 1% and not significantly different

And despite the fact that none of the improvements did result in significantly improved 30m sprint times  (A: 0.23%; B: 0.13%; C: 0.33%; D: −0.68%; E −0.91%), there were statistical significant differences in the dynamic strength / power (measured via 1-RM full squats), as well as the maximal velocity of displacement during the full squat (a measure of the explosiveness), between the five study arms that may give us some clues in terms of what type of training could promote your individual training goals best.
Figure 1: Relative changes in full squat 1RM and full squat velocity (left) and ratio of power (1RM) and explosiveness (velocity) improvements (right) after 7 weeks on the 5 different protocols (based on Sáez de Villarreal. 2012)
So what exactly are the implications for your training regimen, then? Well, lets start with the most obvious things first - so, let's assume that you ...
  • want to become more explosive; in that case, you would perform regimen C, because despite the fact that regimen E may be similarly specific (see figure 1, right), the overall increase in full squat velocity with C was 33% greater than with regimen E (25% vs. 16%). 
  • want to improve your overall power; in that case you would perform regimen A, because neither the classic power protocol B nor the surprisingly power-specific CMJloaded protocol D (see video 1) elicit similarly pronounced gains in 1-RM squat performance as the combined protocol.
And what if you want to do both - get stronger and faster? Well the answer should be easy: Protocol A! After all, it did not just produce the most pronounced strength gains, it is also a very close second (+22% vs. +25%) as far as the improvements in explosiveness are concerned.

But that's unfair - the volume was much higher!  

Image 2 (muscle-fitness-tips.net): Plyos make an excellent addition to every routine, no matter if you want to gain muscle, build strength or agility or just don't want to do the same boring workout all the time. If you need some inspiration on which ones you could simply add to your current routine, check out the exrx.net list and pick your favorites.
Yeah, that's right... and that's not even all you would have to consider before you draw otherwise foregone conclusions based on the results of the study at hand. Despite the fact that the study participants were trained individuals, for example, their 1RM squat performance at the beginning of the study was (only) roughly their body weight, so that there was still more than enough room for improvements (what's your squat?). The testing procedure, the 1-RM full squat, as another example, is - at least in my humble opinion  - not the very best method to test "real" strength gains as it requires a decent amount of proficiency to be performed correctly. If you are a power lifter and squatting is part of your competition, fine - otherwise, testing leg-strength / power with 1-RM squats always reminds me of telling Mr Average Joe to sprint 100m as fast as he can, while dribbling a soccer ball... nonsensical? Well, so is the 1-RM squat performance test.

I could probably come up with a dozen of other "confounding factors" and "things to consider", but in the end we have to cope with what we have and based on the data from this study it does not appear to be too far-fetched that you could also benefit from incorporating some explosive CMJs (or jump squats) and plyometrics into your regimen - even if it was for nothing else than a speed and agility building, fat burning body weight based HIIT protocol you can perform at the end of your regular workout sessions and even when you are traveling!

Additional resources:

ChestBicepsBackCoreLegsTricepsShoulders
In case you are looking for the best classic exercises click on the body part above to see the most effective ones

References:

  1. ExRx.net. Plyometrics and Power Exercises: Instruction and Movement Analysis. < http://www.exrx.net/Lists/PowerExercises.html > retrieved July 15, 2012.
  2. Sáez de Villarreal E, et al. Enhancing sprint and strength performance: Combined versus maximal power, traditional heavy-resistance and plyometric training. J Sci Med Sport. 2012.
  3. SportStrong.uk. Loaded Countermovement Jump. YouTube Video < youtube.com/?v=f69faqO1tto > retrieved July 15, 2012.