REACTIVE STRENGTH

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REACTIVE STRENGTH

• ADRIAN FACCIONI
• UNIVERSITY OF CANBERRA
• CENTRE FOR SPORTS STUDIES

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REACTIVE STRENGTH

• STRETCH SHORTENING CYCLE
• STRETCH REFLEX
• MYOTATIC REFLEX
• PLYOMETRICS

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REACTIVE STRENGTH

• DEFN.
• A CONCENTRIC CONTRACTION FOLLOWING A RAPID
  ECCENTRIC CONTRACTION RESULTS IN GREATER
  CONCENTRIC FORCE OUTPUT. (Cavagna et al 1965)

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PHYSIOLOGY BEHIND REACTIVE STRENGTH.

• LENGTHENING OF THE MUSCULOTENDINOUS SYSTEM.
  PRODUCES PASSIVE ELASTIC STRENGTH ADDED TO
  VOLUNTARY MUSCULAR STRENGTH.

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PHYSIOLOGY BEHIND REACTIVE STRENGTH.

• LENGTHENING OF THE MUSCLE ACTIVATES THE MUSCLE
  SPINDLE REFLEX WHICH IN TURN LEADS TO AN
  INVOLUNTARY MUSCULAR CONTRACTION COMBINED WITH
  THE VOLUNTARY CONTRACTION.

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PHYSIOLOGY BEHIND REACTIVE STRENGTH.

• INCREASED FORCE OUTPUT DUE TO THE LENGTH-TENSION
  RELATIONSHIP OF MUSCLE TISSUE.

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PHYSIOLOGY BEHIND REACTIVE STRENGTH.

• LONG TERM PLYOMETRIC TRAINING IS BELIEVED TO
  DECREASE THE INHIBITORY EFFECTS OF THE GOLGI
  TENDON ORGAN ALLOWING A GREATER MUSCLE STRETCH
  THEREFORE INCREASING THE RATE OF IMPULSE OF THE
  MUSCLE SPINDLE TO THE MOTOR UNIT.

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LONG VS SHORT SSC.

• SHORT SSC USED IN SPRINTING, GYMNASTS, JUMPERS,
  ETC.
• LONG SSC (?) VOLLEYBALL JUMP, ETC.
• I CLASSIFY THE LONG SSC AS AN EXPLOSIVE STRENGTH
  ACTIVITY RATHER THAN A REACTIVE STRENGTH ACTIVITY.

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PROGRAM CONSIDERATIONS

• SPECIFICITY
• HORIZONTAL VS VERTICAL AND LATERAL MOVEMENTS.
• HORIZONTAL MORE EXPLOSIVE STRENGTH UNLESS SPEED
  BOUND.
• VERTICAL MOST INTENSE.
• LATERAL IMPORTANT FOR Eg. TEAM SPORTS.

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OTHER REACTIVE TRAINING METHODS.

• OVERSPEED RUNNING (REACTIVE STRENGTH - NEURAL)
• RESISTED RUNNING (EXPLOSIVE STRENGTH)
• UPPER BODY REACTIVE STRENGTH
• PUSHUPS, MEDBALL PASSES
• SLIGHTLY HEAVIER IMPLEMENTS Eg. RACQUETS, BATS,
  CLUBS ETC.

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TRAINING/SAFETY GUIDELINES.

• TRAINING AGE OF THE ATHLETE.
• ANY AGE. AS LONG AS LOW INTENSITY AND
  PROGRESSIVE.
• VOLUME
• 30-50 TOUCHDOWNS BEGINNING.
• ONLY LIMITED BY PRIOR CONDITIONING. KEY IS
  QUALITY MUST BE EVIDENT AT ALL TIMES.

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TRAINING/SAFETY GUIDELINES.

• ORDER OF INTENSITY.
• D/L VERTICAL (Low Impact)
• A/L HORIZONTAL
• D/L VERTICAL (High Impact)
• S/L HORIZONTAL
• S/ L VERTICAL (High Impact)
• SHOCK JUMPS
• DEPTH JUMPS (D/L - S/L)

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TRAINING/SAFETY GUIDELINES.

• INTENSITY.
• MUST BE 100 AT ALL TIMES.
• IF SPEED STRENGTH (EXPLOSIVE) JUMPS, THE
  INTENSITY CAN BE LESS.
• FREQUENCY.
• LIMITED TO 2-3 DAYS PER WEEK.

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SQUAT PLYOMETRIC STUDY (OSHEA ET AL 1990)

• SQUAT GROUP
• 3.30CM IMPROVEMENT
• PLYOMETRIC GROUP
• 3.81CM IMPROVEMENT
• SQUAT-PLYOMETRIC GROUP
• 10.67CM IMPROVEMENT.

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STRENGTH TRANSFER TO REACTIVE STRENGTH.

• BALYI (1992) SUGGESTED THAT COMBINING SPEED RUNS
  WITH PLYOMETRIC JUMPS AND WEIGHTS MAXIMISED
  STRENGTH TRANSFER TO SPRINT PERFORMANCE.
• ORDER MAX WEIGHTS-PLYOMETRIC JUMPS-MAXIMAL
  SPRINTS.

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TRAINING/SAFETY GUIDELINES.

• RECOVERY.
• 3-8 MINUTES BETWEEN SETS.
• 2-4 DAYS BETWEEN TRAINING SESSIONS.
• STRENGTH REQUIREMENTS.
• RUSSIANS 2-2.5 x BODY WEIGHT SQUAT
• WHY? DEPTH JUMPS FROM 3.2m
• MID-TORSO STRENGTH VERY IMPORTANT.

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SCHMIDTBLEICHER AND GOLLHOFER (1988)

• NEURAL INHIBITION JUST PRIOR TO GROUND CONTACT.
• INCREASES STRESS ON SKELETAL SYSTEM.
• WITH TRAINING INHIBITION DECREASES, MORE MUSCULAR
  SUPPORT WITH PLYOMETRICS.

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TRAINING/SAFETY GUIDELINES.

• INJURY CONTRAINDICATIONS.
• PREVALENT IN ANKLE, KNEE, HIP AND LUMBAR/SACRAL
  REGION AND ANTERIOR AND LATERAL FASCIAL
  COMPARTMENTS OF LOWER LIMB.
• OVERLOAD IS THE MAIN CONTRIBUTOR TO PLYOMETRIC
  INJURY. TOO MANY JUMPS, TOO INTENSE, INADEQUATE
  RECOVERY B/W SESSIONS, TOO MUCH OTHER DEMANDING
  MUSCULOSKELETAL TRAINING.

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TRAINING/SAFETY GUIDELINES.

• PERFORMANCE ERRORS.
• IF HEEL TOUCHES THE GROUND
• TOO MUCH COLLAPSE THROUGH KNEE AND HIP JOINT
• NOT MAINTAINING SOLID PILLAR
• TRAINING EQUIPMENT.
• GOOD SHOES
• SOLID SURFACE (SPRUNG FLOOR, TARTAN ETC.)

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CUES FOR TEACHING PLYOMETRICS.

• GROUND IS LIKE A HOT PLATE
• ROCK SOLID THROUGH PILLAR REGION.
• ANKLES STIFF AND RIDGID