Ch16 Plyometrics

What explains the increased power production seen with plyometrics program?

- The Mechanical Model of Plyometric Exercise - Neurophysiological Model of Plyometric Exercise

What sports is this good for & what season is best for ?

anaerobic sports & towards end offseason

What is the primary component of contractile component?

Actin, Myosin is the primary source of muscle force during concentric muscle action.

What amount of rest would be MOST appropriate to assign to a low intensity plyometric drill lasting 20 seconds? a. 1 minute b. 200 seconds c. 100 seconds d. 30 seconds

100 seconds

Which of the following work-to-rest ratios is the MOST appropriate to assign to a plyometric training workout? a. 1:5 b. 1:4 c. 1:3 d. 1:2

1:5

What is the recommended surface to do pylo?

A grass field, suspended floor, or rubber mat is a good surface choice.

How do you measure intensity when designing plyometric exercises?

A) Points of contact (1 leg vs 2 legs) B) Speed C) Height of drill (center of gravity) D) Subjects weight

Which of the following should be assessed before beginning a lower body plyometric training program? I. balance II. strength III. speed IV. lean body mass a. I and III only b. II and IV only c. I, II, and III only d. I, II, III, and IV

D) I, II, III, IV Balance, Strength, Speed, Lean Body Mass

6. Which of the following types of plyometric drills is generally considered to be the MOST intense? a. jumps in place b. bounds c. depth jumps d. box jumps

Depth Jumps

Explain the mechanical model of plyometric exercise

Elastic energy in tendons and muscles is increased with a rapid stretch (as in an eccentric muscle action) and then briefly stored. - If a concentric muscle action follows immediately, the stored energy is released, contributing to the total force production.

What is the primary component of parallel elastic component?

Epi, Peri & Endomysium The parallel elastic component exerts a passive force with unstimulated muscle stretch

Equipment & depth jumping

Equipment • Boxes used for box jumps and depth jumps must be sturdy and should have a nonslip top. • Boxes should range in height from 6 to 42 inches • Boxes should have landing surfaces of at least 18 by 24 inches Depth Jumping • The recommended height for depth jumps ranges from 16 to 42 inches, with 30 to 32 inches being the norm. • Depth jumps for athletes who weigh over 220 pounds should be 18 inches or less.

What are some lower body plyometric exercises? Which is lowest intensity? Which is highest intensity?

Jumps in place - Jumping and landing on same spot • Standing Jumps - Maximal effort jumps w/ horizontal or vertical component emphasis • Bounds - Exaggerated movement with greater horizontal speeds • Box Drills - Higher intensity jumps using a box • Depth Jumps - Highest intensity type of drill; involves dropping/jumping off from a box with increased height

Explain the neurophysiological model of plyometric exercise

Makes use of the Stretch reflex: the body's involuntary response to an external stimulus that stretches the muscles. - When muscle spindles are stimulated, the stretch reflex is stimulated, sending input to the spinal cord via Type Ia nerve fibers. - After synapsing with the alpha motor neurons in the spinal cord, impulses travel to the agonist extrafusal fibers, causing a reflexive muscle action.

What is the frequency for designing plyometric exercises? What is the work to rest ratio? What is the recovery?

Rest 48-72 hours betweensessions 2 -4 Plyometric sessions x week 6 - 10 week cycles* Recovery Repetitions Low I- N/A High I - 5-10 sec Sets W:R Ratio 1:5 - 1:10

What is the purpose of plyometric exercise?

The purpose of plyometric exercise is to increase the power of subsequent movements by using both the natural elastic components of muscle and tendon and the stretch reflex

What is the stretch shortening cycle? What are the 3 phases?

The stretch-shortening cycle (SSC) employs both the energy storage of the SEC and stimulation of the stretch reflex to facilitate maximal increase in muscle recruitment over a minimal amount of time. - There are three phases: eccentric, amortization and concentric.

How do you measure volume when designing plyometric exercises?

Volume Beginner 80 - 100 contacts / 30M Intermediate 100-120 contacts/ 30-70M Advanced 120-140 contacts/ 70-100 M

Can you implement resistance training with plyometrics?

Yes but its not recommended to do both resistance training and pylometrics on the same day?

1. All of the following are phases of the stretch shortening cycle EXCEPT a. amortization. b. concentric. c. eccentric. d. isometric.

isometric

What are some upper body plyometric exercises?

medicine ball throws • catches • several types of push-ups

2. Which of the following structures detects rapid movement and initiates the stretch reflex? a. Golgi tendon organ b. muscle spindle c. extrafusal muscle fiber d. Pacinian corpuscle

muscle spindle

4) Which of the following is the BEST surface on which to perform lower body plyometric drills? a. trampoline b. exercise mat c. asphalt d. suspended wood floor

suspended wood floor

3. Which of the following is a primary component of the series elastic component? a. tendon b. muscle fiber c. actin d. ligament

tendon

Whose at a increased risk for injury when doing pylo? How many inches should they not do from depth jumps from heights greater than?

• Athletes who weigh more than 220 pounds (100 kg) may be at an increased risk for injury when performing plyometric exercises. • Further, athletes weighing over 220 pounds should not perform depth jumps from heights greater than 18 inches