Plyometrics represent high intensity training, placing great stress on the bones, joints, and connective tissue. While plyometrics can improve an athlete’s speed, power, and performance, they also place her or him at greater risk of injury than less intense training exercises. Therefore, certain guidelines need to be followed to prevent injuries during training.
Sport-Specific Movements - The training exercises should mimic the movements in the athlete's sport (mechanical, physiological and metabolic similarity).
Functional Strength - The athlete should display adequate eccentric, isometric and concentric functional strength during movements. This allows for optimal neuromuscular efficiency and produces greater force production (concentric contractions). Also, optimum eccentric strength (force reduction) allows for efficient use of stored elastic potential energy and greater concentric contractions.
Kinetic Chain Structural and Functional Efficiency - When the neuromuscular system performs functional activities (body movements) with the least amount of energy and stress on the kinetic chain, functional efficiency is achieved. When the kinetic chain is properly aligned during static, transitional and dynamic movements, structural integrity is achieved.
Stabilization Strength - Adequate amounts of core strength and neuromuscular efficiency decrease the amortization phase (time between the eccentric contraction and the concentric contraction).
Training progressions should follow this path:
1. Simple to Complex 2. Stable to Unstable 3. Body Weight Exercises to Resistance Exercises 4. Low Loads to High Loads
Signs of over-training include:
1. Prolonged foot contact with the ground 2. Lack of control 3. Decreased vertical height or horizontal distance 4. Longer rest periods are needed by the athlete
Safety concerns during plyometric training are:
1. Proper footwear for the athlete 2. Proper training surfaces (hard surfaces should be avoided) 3. Program design and supervision by a fitness professional
Part 4 in this series will detail popular plyometric exercises.