This is an excerpt from Complete Conditioning for Hockey by Peter W. Twist.
Over the past decade, plyometric training has become an integral part of athletics training programs for coaches in most multidirectional sports. Strength and explosive power are the foundation for success in anaerobic (sprinting energy systems) sports such as hockey, rugby, basketball, and football. Today all top hockey coaches and trainers integrate plyometrics into their hockey-specific conditioning programs. Their goal is to take weight room strength gains and better express explosive power on the ice in the form of stops and starts, aggressive exits out of turns, slap shots, bodychecks, and dynamic skating patterns.
Plyometric training refers to a distinct method of training for power or explosiveness. It is a method of training, not a specific exercise. Jump training in the 1970s targeted depth drops from high heights converted into vertical jumps and massive bounding drills. Coaches today prescribe exercises more specific to hockey, including single-leg multidirectional moves, lateral moves, and whole-body rotary power. Emphasizing the appropriate intensity on the landing and loading of the legs prevents deceleration injuries and forms the base to drive up acceleration.
I measure plyometric intensity by the impact caused by the amount of displacement. A jump from a greater height will, by nature, impose greater stress on the muscles, ligaments, and bones. For me, the risk outweighs the benefit. When jumping and bounding, the joints must absorb body weight as it lands on the ground. This impact can greatly stress the joints. The greater the height of the jump, the more force the ankle, knee, hip, and spine have to endure. Also, the more an athlete weighs, the greater the risk of injury. Players who weigh 220 pounds (100 kilograms) stress their joints far more than do players who weigh 170 pounds (77 kilograms). And the lower the relative strength, the greater the risk of injury. Players who weigh 170 pounds and lack sufficient muscle development and leg strength are also at risk.
Players in the pubertal phase of growth and maturation, who are developing longer skeletal levers but have not yet built muscles of corresponding mass and strength, experience their peak height velocity. The joints connecting longer bones are less able to handle lateral deceleration forces; epipheaseel growth plates do not like repeated high impact; and a player’s new height throws off his mechanics. Traditional plyometrics must be avoided during this period of awkward growth when players are more susceptible to injury.
Many athletes have participated in traditional plyometrics and netted excellent gains without injury. But today’s plyometric exercise options reduce the risk of injury. Most modern plyometric drills were created with the dual goal of producing sport-specific benefits and improving explosiveness without totally thrashing the legs, training for results but with consideration for decreasing the recovery time. This attribute is important for hockey players, who also tax their legs by doing strength training, anaerobic sprint intervals, balance drills, agility drills, speed training, on-ice practice, and power skating. Multisport athletes face these daily demands all year long.
Thrashing is a nonscientific term, but it accurately describes the level of stress that high-impact plyometrics impose on the legs. Regeneration time is required to repair and prepare for more physical challenges during the next workout, practice, or game.
A quick, easy generalization to help differentiate between plyometric exercises for first-step quickness and plyometric exercises for speed focuses on the depth of landing, the effort required to initiate power, and the focus on powering through triple extension. In training stride power for speed, players land or stop lower (deep) and power back the opposite way through a full stride. For pure quickness, they strive to pop the feet off the ground immediately, coupling the eccentric and concentric phases. In quickness plyometrics, the hips drop only slightly and the knees flex just a couple of inches (5 centimeters). First-step quickness and foot rapidity are trained through two key methods: short-range plyometric coupling and lightning foot repeat drills.
This is an excerpt from Complete Conditioning for Hockey.