Multi-Dimensional Concept of Power Implications for Training and Performance CRAIG J. CISAR, Ph.D. CSCS, *D, NSCA-CPT, *D DEPARTMENT OF KINESIOLOGY SAN JOSE STATE UNIVERSITY DEFINITION OF POWER • WORK/TIME • WORK = FORCE X DISTANCE • (FORCE X DISTANCE)/TIME • VELOCITY = DISTANCE/TIME • FORCE X VELOCITY FACTORS LIMITING POWER • FORCE • CONTRACTILE PROTEIN IN SARCOMERE • ACTIN • MYOSIN NOTE: TOTAL FORCE = ACTIN & MYOSIN BINDING PLUS ELASTIC STORED ENERGY FACTORS LIMITING POWER • ELASTIC STORED ENERGY LOCATED IN • MUSCLES • TENDONS NOTE: ELASTIC ENERGY IN TENDONS HAS GREATER FORCE POTENTIAL THAN ELASTIC ENERGY IN MUSCLES, BUT IS LIMITED IN USE DUE TO THE NECESSITY TO OPTIMIZE COORINATED MOVEMENT FORM FACTORS LIMITING POWER • STRETCH REFLEX MECHANISM • PRESTRETCH OF MUSCLE TO 120% OF NORMAL RESTING MUSCLE LENGTH • MORE OPTIMAL BINDING OF ACTIN AND MYOSIN • MUSCLE SPINDLES DETECT STRETCH EVOKING REFLEX CONTRACTION BY THE STRETCHED MUSCLE EXAMPLES: (1) CONTRACTING AGONIST STRETCHES ANTAGONIST AND (2) DURING THE ECCENTRIC PHASE OF PLYOMETRICS FACTORS LIMITING POWER • MOVEMENT SPEED AND REACTION TIME • CENTRAL AND PERIPHERAL NERVOUS SYSTEMS • NEUROTRANSMITTER CONCENTRATIONS • MYELINATION OF AXONS • INTRAMUSCULAR ENZYME CONCENTRATIONS OF PHOSPHAEN (ATP-PC) METABOLISM • MYOSIN ATPASE • CREATINE PHOSPHOKINASE • ADENYLATE KINASE WAYS TO IMPROVE POWER INCREASED FORCE (I.E., STRENGTH) PRODUCTION CAPABILITES • NEURAL ADAPTATIONS • CENTRAL NERVOUS SYSTEM • ENHANCED ACTIVATION OF MOTOR TRACTS FROM THE PRIMARY AND PREMOTOR CORTEXES • PERIPHERAL NERVOUS SYSTEM • INCREASED RECRUITMENT OF MOTOR UNITS INCREASED FORCE (I.E., STRENGTH) PRODUCTION CAPABILITES • INCREASED CONTRACTILE PROTEIN VIA MUSCLE HYPERTROPY (I.E., MUSCLE FIBER SIZE) • HIGH VOLUME STRENGTH TRAINING PROGRAM • INCREASED HYPERPLASIA (I.E., MUSCLE FIBER NUMBER) • HIGH INTENSITY STRENGTH TRAINING PROGRAM >NEURAL ADAPTATIONS>HYPERTROPHY>HYPERPLASIA INCREASED FORCE (I.E., STRENGTH) PRODUCTION CAPABILITES • MUSCLE FIBER TYPE AND SPEED OF MOVEMENT • FAST-TWITCH MUSCLE FIBERS = GREATER FORCE PRODUCTION • FAST-TWITCH MUSCLE FIBERS = FASTER SPEED OF CONTRACTION • FAST-TWITCH MUSCLE FIBERS = GREATER FORCE PRODUCTION AT FASTER SPEEDS OF MOVEMENT MUSCLE FIBER TYPE AND SPEED OF MOVEMENT INCREASE MOVEMENT SPEED (I.E., VELOCITY) AND ACCELERATION • MUSCLE FIBER TYPE • FAST-TWITCH MUSCLE FIBERS = FASTER SPEED OF CONTRACTION MUSCLE FIBER TYPE INCREASE MOVEMENT SPEED (I.E., VELOCITY) AND ACCELERATION • FORCE VERSUS RESISTANCE • INCREASED FORCE AND/OR DECREASED RESISTANCE = INCREASED MOVEMENT SPEED • ACCLERATION = FORCE/MASS • INCREASED FORCE AND/OR DECREASED MASS (E.G., FAT MASS) = INCREASED ACCELERATION INCREASE MOVEMENT SPEED (I.E., VELOCITY) AND ACCELERATION • COORDINATION • SYNCHRONUS RECRUITMENT OF MOTOR UNITS • AGONIST MUSCLE VERSUS ANTAGONIST • BALANCED INTERACTION BETWEEN AGONISTIC MUSCLE AND ANTAGONIST MUSCLE INCREASE MOVEMENT SPEED (I.E., VELOCITY) AND ACCELERATION • DECREASE REACTION TIME AND HENCE MOVEMENT TIME • CENTRAL AND PERIPHERAL NERVOUS SYSTEMS ADAPTATIONS • INCREASE DISTANCE OF FORCE APPLICATION • TRAINING • DEVELOPMENT MOVEMENT SKILLS AND TECHNIQUE POWER NEEDS ANALYSIS FORCE VERSUS VELOCITY PERCENT OF MAXIMAL POWER VERSUS VELOCITY TRAINING AND PERFORMANCE IMPLICATIONS SPECIFICIY OF TRAINING • FORCE VERSUS VELOCITY • NEEDS ANALYSIS • HIGHER FORCE CAPABILITIES AT SLOWER VELOCITY OR LOWER FORCE CAPABILITIES AT FASTER VELOCITY OR BOTH? • CAN EITHER END OF THE FORCE VELOCITY CONTINUUM BE IGNORED? SPECIFICIY OF TRAINING • NEEDS ANALYSIS • WHICH MUSCLE GROUPS NEED TO BE POWER TRAINED? • DOES THE POWER TRAINING NEED TO BE SIMILAR FOR ALL MUSCLE GROUPS? • CAN ANY MUSCLE GROUPS BE IGNORED IN TERMS OF POWER TRAINING? SPECIFICIY OF TRAINING • NEEDS ANALYSIS • RANGE OF MOTION • THROUGH WHAT RANGE OF MOTION DOES POWER NEED TO BE DEVELOPED? • BE CREATIVE IN SELECTING AND DEVLOPING EXERCISE TRAINING TECHNIQUES THAT MIMIC THE REQUIRED RANGE OF MOTION SPECIFICIY OF TRAINING CLOSED-CHAIN VERSUS OPEN-CHAIN KINETIC EXERCISES SPECIFICIY OF TRAINING • CLOSED-CHAIN KINETIC EXERCISES • IN CLOSED-CHAIN EXERCISES THE DISTAL SEGMENT (E.G., HAND OR FOOT) IS FIXED WHILE THE PROXIMAL SEGMENT MOVES • EXAMPLE: IN WEIGHT BEARING EXERCISES THE BODY MOVES OVER THE HAND OR FOOT • NO LINK WITHIN THE CHAIN CAN MOVE INDEPENDENTLY OF THE OTHERS; ALL ARE AFFECTED BY MOVEMENT OF ONE SEGMENT SPECIFICIY OF TRAINING • OPEN-CHAIN KINETIC EXERCISES • IN OPEN-CHAIN EXERCISES THE DISTAL SEGMENT MOVES FREELY IN SPACE • IN OPEN-CHAIN EXERCISES THE MOTION OF ADJACENT JOINTS IS NOT PREDICTABLE AS THEY MAY MOVE INDEPENDENTLY OR TOGETHER SPECIFICIY OF TRAINING • CLOSED-CHAIN KINETIC EXERCISES • LOWER-EXTREMITY MOVEMENTS IN SPORTS ARE PRIMARILY CLOSED-CHAIN • CLOSED-CHAIN EXERCISES CAN BE USED TO IMPROVE STRENGTH, POWER, STABILITY, BALANCE, CORDINATION, AND AGILITY • CAPABLE OF GENERATING LARGE FORCES BUT AT SLOWER VELOCITIES • MORE BALANCED MUSCLE ACTIVATION AND FORCE PRODUCTION • CONSIDERED TO BE MORE FUNCTIONAL SPECIFICIY OF TRAINING • OPEN-CHAIN KINETIC EXERCISES • PRODUCE HIGH VELOCITY MOVEMENTS SUCH AS THROWING OR KICKING A BALL, SWINGING A GOLF CLUB OR BAT, OR SWINGING THE LEG DURING RUNNING OR ARM DURING SWIMMING • HENCE, IMPORTANT DURING MANY SPORTS AS WELL AS DAILY ACTIVITIES • BETTER AT ISOLATING MUSCLES THAT ARE WEAK SPECIFICIY OF TRAINING CLOSED-CHAIN VERSUS OPEN-CHAIN KINETIC EXERCISES • NEEDS ANALYSIS • WHICH TYPE OF CHAIN KINETICS NEEDS TO BE DEVELOPED? • OPEN CHAIN OR CLOSED CHAIN OR BOTH? • BE CREATIVE IN SELECTING AND DEVELOPING EXERCISE TRAINING TECHNIQUES THAT MIMIC THE REQUIRED CHAIN KINETICS SPECIFICIY OF TRAINING • FAST-TWITCH MUSCLE FIBER TYPE • GREATER FORCE • GREATER SPEED (I.E., VELOCITY) • GREATER POWER • CAN TRAINING INCREASE THE SIZE (HYPERTROPHY) AND/OR NUMBER (HYPERPLASIA) OF FAST-TWITCH MOTOR UNITS? • HYPERTROPHY HAS LONG BEEN ACCEPTED • HYPERPLASIA DOCUMENTED IN CROSSSECTIONAL AND LONGITUDINAL STUDIES • CAN TRAINING CHANGE MUSCLE FIBER TYPE? • MUSCLE FIBER TYPE CONVERSION HAS BEEN QUESTIONED MUSCLE FIBER TYPE CONVERSION SPECIFICIY OF TRAINING • PHOSPHAGEN (ATP-PC) ENERGY SYSTEM • HIGHEST POWER (KCAL/SEC) • LOWEST CAPACITY (TOTAL KCAL) • PRIMARY ENERGY SYSTEM USED IN POWER ACTIVITIES • DEVELOPMENT OF ATP-PC ENERGY SYSTEM • HIGH INTENSITY, SHORT DURATION ACTIVITY • LONGER REST PERIODS TO REPLENISH ATP-PC • 25-30 SECONDS TO REPLENISH 50% • 2-3 MINUTES TO REPLENISH 100% GENERAL TRAINING GUIDELINES • HIGH FORCE DEVELOPMENT CONCENTRIC STRENGTH TRAINING • 2-4 SETS USING A 2-4 RM (90-95% OF 1-RM) WORKLOAD PERFORMED 3-5 DAYS PER WEEK WITH A 2-5 MINUTE REST PERIOD • MOST FREQUENTLY USED WITH MULTIJOINT, CORE EXERCISES (I.E., MULTIJOINT EXERCISES INVOLVING ONE OR MORE LARGE MUSCLE GROUPS) FOR SINGLE-EFFORT EVENTS GENERAL TRAINING GUIDELINES • HIGH SPEED DEVELOPMENT CONCENTRIC STRENGH TRAINING • 2-4 REPETITIONS PER SET, 3-4 SETS PER EXERCISE USING A 30-60% 1-RM WORKLOAD WITH A 2-5 MINUTE REST PERIOD • USED WITH MULTI-JOINT POWER EXERCISES (E.G., POWER SNATCH, POWER CLEAN, HANG CLEAN, PUSH JERK, AND PUSH PRESS) FOR MULTIPLE-EFFORT EVENTS AGAINST A MODERATE (60% 1-RM WORKLOAD) TO LIGHT (30% 1-RM WORKLOAD) RESISTANCE GENERAL TRAINING GUIDELINES • PLYOMETRIC TRAINING • IN-PLACE, SHORT RESPONSE, AND LONG RESPONSE EXERCISES • LOWER BODY EXERCISES INVOLVING QUICK FEET MOVEMENTS, SKIPS, HOPS, JUMPS, AND BOUNDS WITH OR WITHOUT CONES, HURDLES, BOXES, ETC. • UPPER BODY EXERCISES INVOLVING MEDICINE BALLS AND BODY WEIGHT WITH OR WITHOUT BOXES GENERAL TRAINING GUIDELINES • SPEED TRAINING • SHORT INTERVAL, REPETITION TRAINING USING WORK BOUTS OF 2-3 SEC UP TO 30 SEC WITH A WORK:REST RATIO OF 1:3 OR 1:5 AND A PASSIVE RECOVERY • ACCELERATION SPRINTS - GRADUAL INCREASES IN SPEED FROM JOGGING TO STRIDING TO SPRINTING IN 50-100 METER SEGMENTS GENERAL TRAINING GUIDELINES • SPEED TRAINING • HOLLOW SPRINTS - TWO SPRINTS WITH A PERIOD OF WALKING OR JOGGING IN BETWEEN BETWEEN EACH SPRINT • SPEED TRAINING - REPEATED SHORT, MAXIMAL SPRINTS WITH COMPLETE RECOVERY BETWEEN EACH SPRINT • OTHER SPEED DRILLS GENERAL TRAINING GUIDELINES • AGILITY TRAINING • IMPROVE REACTION TIME • IMPROVE EXPLOSIVE CHANGE OF DIRECTION CAPABILITIES • FLEXIBILITY TRAINING • IMPROVE DISTANCE THROUGH WHICH FORCE CAN BE EXPLOSIVELY APPLIED • BALANCE TRAINING • PROVIDE A STATIC AND DYNAMIC FOUNDATIONAL PLATFORM FOR EXPLOSIVE MOVEMENT EXAMPLES OF TRAINING MODALITIES • BODY WEIGHT • WEIGHTED CHEST VESTS • ANKLE AND WRIST WEIGHTS • BARBELLS AND DUMBBELLS • MEDICINE AND KETTLE BALLS EXAMPLES OF TRAINING MODALITIES • OTHER EQUIPMENT TO IMPROVE STRENGTH, SPEED, AGILITY, AND/OR BALANCE • RUBBER BANDS AND TUBING • BOXES, STEPS, HURDLES, AND CONES • SLIDE BOARDS • LADDERS • RINGS AND DOTS • TUBING/CORDS, HARNESSES, AND BELTS • PARACHUTES (E.G., POWER CHUTES) • MATS AND STABILITY BALLS • BALANCE ROLLERS, DISCS, BEAMS, AND BOARDS • OTHER - BE CREATIVE AND HAVE FUN! THANK YOU VERY MUCH! QUESTIONS??