The term plyometrics plyometric is Greek. It comes from two words meaning greater, longer, wider and to measure, to appraise, to compare. It was used describe the greater tension that could be developed in muscles when a quick stretching phase is followed by a fast contraction (Zannon 1989). You can describe any exercise (plyo box jump) or movement which a person is taking advantage of the stretch-shorting cycle of a fast twitch muscle during an explosive movement. Plyometric training has been around for a number of years but it had got a bad rep for it miss use. Due to the number of injuries that have come about from people miss using plyometrics in there training.
The main reason for this is the miss understanding of the stretch reflex and the recovery time needed for these explosive movements. The first time to understand when talking about the stretch reflex is the releshinship of the muscles. The main muscle in the movement (the agonist), for example, the quads in a plyo box jump, and the antagonist which is the relaxing muscle of the movement, the hamstrings in a plyo box jump.
When the quadriceps muscle to contract and the Achilles tendon and patella tendon feel the push from the floor. It causes the quadriceps to stretch which results in activation of the sensory spindle receptors in the muscle. Within the muscle, you have collars which are referred to as spindles. They are very sensitive and reactive causing them to contract or relax from very little stimulating.
During the plyo box jump, a message a message is sent to the spinal cord to communicate a fast action is about to happen and stability of the joints is going to need to compete for this movement and protect the joint and muscles.
Best Wodden Plyo box
- MAXIMUM EFFORT WITHOUT FEAR: The rounded wood plyo box corners guarantee you can put in maximum effort with every jump because you won’t get hurt.
- – DRASTICALLY IMPROVED SPORTS PERFORMANCE: Perform a huge selection of exercises on the plyo jump box drastically improving your jumping ability no matter what your sport.
- – 3 SIZES FOR THE PRICE OF 1: Save huge money and space, because the plyometric workout box comes in 3 of the most popular sizes available (20″ x 24″ x 30″), (18″x20″x24″), or (12″x14″x16″)
- SAFE AND STABLE: Because our boxes are rated to 400lbs, you can jump and step up with confidence. Plus, the edges and corners are rounded to prevent scrapes on missed jumps. Easily move them around your gym with the convenient carry handles.
- EASY TO ASSEMBLE AND USE: Each box is built with a unique, interlocking design from the highest grade ¾” plywood panels. The sections fit together like a basic puzzle and have pre-drilled holes to guide you through simple, drill-free assembly. Once assembled, use any side for plyometric exercises depending on how much effort your workout demands. Each box has 3 different heights to choose from!
- BUY WITH CONFIDENCE: Rep Fitness is a full-service equipment company based in Denver, Colorado.
- 20″ x 24″ x 30″ wooden plyo jump box
- Ideal tool for cardio and Crossfit plyometric exercises
- Adjustable – 3 heights all in one: 20-Inch, 24-Inch or 30-Inch
- Some Assembly Required
- Pro-duty wooden construction.
- Easy to assemble – Save money and space with 3 box sizes in 1
- Solid wood platform to support heavy weight athletes – Rotate the box for more challenging heights – Hardware included
- Material: Wood – Height: 30″
- Width: 20″ – Length: 24″ – Weight: 58 lbs.
History Of The Stretch-Shorten Cycle
During the 1960s, Professor Rodolfo Margaria of Milan was the first to identify the value of the pre-stretch in producing a strong muscular contraction.Margaria’s work looked at muscular movement as a whole. Based on this work, a length-tension diagram of the working muscle was developed. This allowed for the comparison of the tension in a muscle that had been pre-stretched and
one that had not been pre-stretched. This research was used by NASA to develop the most effective way to walk on the moon (Zanon 1989).
In the 60’s a Russian jump coach by the name of Yuri Verkhoshans developed a plyometric exercise referred to as depth jumping. Which is used on the plyo box across a number of fitness and crossfit gyms. He wanted an exercise that not only strengthened the muscle but also developed the reactive ability needed to decrease the amortization phase. Resistance training improves strength but slows down the reactive ability of the muscle to switch from eccentric to concentric work during the amortization phase. This was his main reason for developing the depth jumping. This exercise not only demands dynamic strength to withstand the landing but also develops the reactive ability of a muscle to switch from eccentric work to concentric work (Verhoshanski 1966).
Performing Depth Jumps (plyo box jump)
He suggested that depth jumps should be performed from a height of .75 to 1.15 meters. Depth jumps from .75 meters height allows the athlete to develop his maximal reactive ability, whereas jumping from 1.15 meters develops more dynamic
strength in the athlete. He stressed that using a height greater than 1.15 makes depth jumping ineffective. The increased height changes the landing mechanism so neither dynamic strength nor reactive ability is gained. The number of repetitions of depth jump to be performed depends on the preparation and strength of the athlete. He recommends for the prepared athlete, two depth jumping sessions a week, with a maximum of 40 repetitions per session(Verhoshanski 1967). Poole and Maneval (1987) also found that two
sessions per week were more effective than three sessions. Depth jumps should be discontinued ten to fourteen days prior to competition.