SKLZ Throwing Plyo Balls five-weight set — 3.5–20 oz progressive resistance, pliable impact-visible training balls

SKLZ Throwing Plyo Balls are a five-weight set of pliable training balls designed to develop pitching mechanics, arm strength, and recovery through overload and underload drills.

These plyo balls provide progressive resistance training using five distinct weights that teach coordination, build power and support post-workout blood flow. Lightweight options reinforce quick, accurate movement patterns and fast-twitch firing, while heavier balls add resistance to boost stamina and throwing velocity. The set ships with guided drills for each weight, and durable, impact-visible material helps you track strike and release during repetition work.

How do different weights improve throwing mechanics?

Varying the ball weight changes the effort and timing needed to complete a throw, forcing refinements in grip, arm path and release. Underload (lighter) balls accelerate the arm and reinforce high-speed mechanics; overload (heavier) balls increase muscular demand, promoting strength through the same movement pattern.

• 3.5 oz and 5.25 oz: speed and quick-twitch timing practice
• 10 oz and 15 oz: progressive resistance to strengthen the acceleration phase
• 20 oz (larger circumference): maximum overload for stamina and power
• Consistent reps across weights to preserve mechanics under load

What drills can I expect and how do they fit into training?

Each ball includes recommended drills that can be mixed into warm-ups, main sessions, or recovery routines. Drills vary from short-distance, high-velocity throws to longer tosses under resistance, letting you target speed, endurance or active recovery on different days.

• Warm-up: light-ball throws to wake up neural pathways
• Main set: alternating heavier and lighter throws for overload/underload cycles
• Recovery: low-intensity, high-repetition tosses to promote circulation
• Progression: follow the provided drills to safely increase load and volume

What are the build and sizing details I should know?

Constructed from a pliable, impact-visible material, the balls are durable for repeated use while letting you see contact and deformation at release. The set is offered in two circumferences: a 9" circumference for lighter weights and a 12" circumference for the heaviest ball, matching handling feel to load.

• Five weights: 3.5 oz, 5.25 oz, 10 oz, 15 oz, 20 oz
• 9" circumference for 3.5–15 oz balls; 12" circumference for 20 oz ball
• Pliable surface shows impact and helps grip consistency
• Durable materials built to withstand repeated training sessions

How should I use this set safely and effectively?

Start with a proper warm-up and use lighter balls to groove technique before adding heavier loads. Increase weight or volume gradually and incorporate rest days; the included drills suggest progressions so you can add intensity without compromising form.

• Begin each session with mobility and light-ball throws
• Progress weight or reps slowly across weeks, not days
• Use heavier balls for short sets to avoid fatigue-driven breakdowns
• Follow cool-down and active recovery routines after heavy work

Who is this for: The SKLZ Throwing Plyo Balls suit baseball and softball athletes, coaches, and throwing specialists who want a structured overload/underload toolset to refine mechanics, develop arm power and maintain circulation during recovery. They also fit training programs for strength & conditioning coaches and rehab professionals looking for versatile, repeatable throwing implements that scale across skill levels.