[quote]Addweight wrote:
Thib:
We know that strength training should be periodized with âstimulus phasesâ
and ârecovery phasesâ.
Do you think that plyometric training and sprints (which are plyometrics,
I believe) should be periodized, or, due to the lack of load, can be trained
âballs-outâ year round?.
How would you periodize that training (in simple terms)?.
Thanks.[/quote]
From one of my articles:
Dumb Thing #6: Misusing Plyometric Training
Iâll start by explaining exactly what plyometric training is, as the term itself has been tagged to several types of training that arenât true plyometric training (e.g. low intensity hops and bounds).
Plyometric training is also known as âshock training.â It was developed by Yuri Verkhoshansky in 1977. The objective of this method is to increase concentric power and force output by stimulating the muscles and reflexes via a âshock stretchingâ action preceding the overcoming portion of the movement.
This is accomplished by dropping from a certain height (typically 0.4m to 0.7m, although heights of up to 1.1m have been used by very advanced athletes) to elicit a powerful stretch activation, then jumping up as high as possible immediately upon landing (or projecting yourself in the air in the case of a depth push-up). The following pictures show the execution of a plyometric/shock exercise known as a depth jump:
Itâs been established in both Eastern and Western studies that depth jumping, or shock training, can significantly increase power production and vertical jump height. This is mostly due to the following factors:
- An increase in reactive strength
Reactive strength refers to the capacity to rapidly switch from an eccentric/yielding action to a concentric/overcoming action. Lack of reactive strength will lead to a longer coupling time and, consequently, lower force and power production during the overcoming portion of the movement (Kurz 2001).
- Neural adaptations
Viitasalo et al. (1998) found a different neural response between athletes doing a lot of jumping and regular individuals when doing a depth jump. Jumpers were able to activate more motor units during the movement (greater EMG) and plan the motor command faster (higher and more rapid pre-action EMG).
KyrölÀinen et al. (1991) also found that 16 weeks of depth jump training led to better jumping efficiency. Schmidtbleicher (1987 and 1982) found that trained subjects were able to use the kinetic energy produced during the eccentric portion of a depth jump, while in untrained subjects this eccentric period was actually inhibiting instead of potentiating!
Finally, Walshe et al. (1998) concluded that the superiority of depth jump training over regular jump training was due to âthe attainment of a higher active muscle state,â meaning that the fast eccentric portion of the movement increased muscle activation.
- Structural adaptations
Depth jumps have been reported to cause some muscle soreness and muscle damage (Horita et al. 1999). This is understandable since the eccentric force produced is very high, albeit rapid. This may indicate that depth jumps are a powerful stimulus to stimulate structural adaptations.
However, depth jumps donât lead to significant hypertrophy. So the nature of the structural adaptations following depth jumping isnât quantitative in nature, but qualitative: an improvement of the strength and contractile capacity of each muscle fiber.
Soviet literature gives the following guidelines when practicing depth jumps:
-
The joint position upon landing should be as close as possible to that of an important sport action (Laputin and Oleshko 1982).
-
The amortization phase should be short enough to avoid losing the elastic energy produced, but long enough to allow for the shock stretching to occur (Laputin and Oleshko 1982). Research indicates that the elastic energy from landing is stored for up to two seconds. So in theory you have a window of two seconds between the landing and take-off phase. However, to maximize the training effect you shouldnât spend more than one second on the floor.
-
The height of the drop should be regulated by the preparedness of the athlete. The heels shouldnât touch the ground during the landing phase. If they do, then the height of the drop is too high (Laputin and Oleshko 1982). A height varying from 0.5m to 0.7m appears to be ideal for most strength and power athletes (Roman 1986).
-
Depth jumps have a very powerful training effect, so the volume of work should be low, i.e. no more than 4 sets of 10 repetitions (or 40 total jumps spread over more sets), two to three times per week for advanced athletes and 3 sets of 5-8 repetitions (or 15-24 total jumps spread over more sets), one to two times per week for lower classes of athletes (Laputin and Oleshko 1982).
-
Because of the very powerful training effect of depth jumping, itâs idiotic to perform this type of training systematically throughout the year. The shock method should be used in blocks of three to four weeks with at least four weeks between blocks (Roman 1986). In fact, some coaches recommend no more than two to three such blocks per year (Medvedyev 1996) and only when a rapid rise in power and reactive strength is needed to further performance gains.
Remember that every training method, regardless of how effective it is, will lose its effectiveness over time. Shock training is no different. If you use it year-round there comes a point where youâll get no added benefits from it. However, by using short âshockâ blocks you can give a quick boost to your performance. Since you only use depth jumps for a short period, youâll get the same performance boost every time you use such a shock block.
The Pet Peeve
Okay, with that out of the way I can discuss the matter of my pet peeve: misused plyometric/shock training. As we saw earlier, shock training can have a very powerful effect on power production, but itâs also very stressful on the myotendinous structures and the joints. This method also leads to very rapid gains in power output, but the gains quickly stagnate and come to a halt.
My biggest problem is with coaches who use plyometric/shock drills too often, for too long, or with an excessive volume. What happened is that somewhere in the late 80s and early 90s, plyos were discovered by North American coaches and seen as one of the secrets of the Eastern block athletes. However, North American coaches are often seduced by the âmore is betterâ approach and started to include way too much volume of plyo work.
The problem with many coaches and athletes is they donât feel that depth jumping (and other shock training) is hard; itâs not very tiring compared to other means of training. Because of this, they feel they can get away with using a super high volume of shock training. Huge mistake!
With plyometric work, more is definitely not better. Quite the contrary, doing too much shock training will lead to structural damage which will lead to overprotective âsafety mechanismsâ (Golgi tendon organs and muscle spindles) which will actually lead to a decrease in power production, not to mention that the risk of injuries increases significantly.
Another related problem is using plyometric training for too long. Shock training is designed to give a quick boost in peak power production. It was used once or twice a year for phases of two to four weeks, not more than that! And it was quite effective when used that way.
Yet nowadays we see North American coaches use plyometric work year round with their athletes. This will diminish the potential benefits of the method. The goal of shock training is to provide a quick boost in power production. If itâs used year round your body gets used to the method as the quick boost effect is thus lost. It can also lead to some degenerative joint problems, especially at the ankle and knee joint.
Finally, another act of stupidity is when coaches use plyometric training during a season. This is beyond idiotic, especially if the sport involves a lot of jumps already (basketball, volleyball, track events, figure skating, gymnastics, etc.). A volleyball player might perform over 400 maximal jumps per week of sport practice; the last thing these athletes need is more jumping! The already high volume of jump and landing work can take its toll on the joints. Adding shock training is a surefire way to lead to a decrease in performance (best case scenario) or an injury (worst case scenario).
Bottom line: Use plyometric/shock training to provide for a needed boost in power production, not as a year-round system (e.g. perform a four week shock training block six weeks prior to an important event; stop two weeks before said event). And when you use it, donât let the amount of fatigue or soreness be your guide to adjusting training volume. Stick to 40-70 total ground contacts per week.