AIS Chapter 13 Strength and power assessment

Strength Definition: ability of a muscle to produce force – Maximal strength – Strength endurance: repeatedly exert submaximal force – Rate of force development (RFD) Isometric strength, measured by hand-held dynamometers Dynamic strength – Isokinetic dynamometry: constant angular velocity – Isoinertial test: constant load, such as 1 RM

Strength Speed-strength, also referred as POWER – Ability to apply force rapidly – Isoinertial protocols that use loads aimed at targeting specific aspects of strength and speed-strength continuum – Squat jump, countermovement jump, for lower body – Bench throw, bench pull, for upper body – Varying in inertial loads Strength endurance – Max number of repetitions in push-ups, chin-ups… – Time to fatigue in submaximal isometric contraction

Strength, power, and functional performance Test results highly correlated with physical performance – Jumping, sprinting Also correlated with skill-dominated activities – Golf club had speed, grinding in sailing Weekly strength training important in maintaining sprint performance across season in team sport athletes Power is usually a more useful discriminator than strength – Strength training more effective for weaker persons – Power training more effective for stronger persons

Test protocols Isometric midthigh pull – – Measure vertical ground reaction force via force platform – Highly related to max strength in dynamic lifts, substitutes to traditional RM testing Maximum strength: 1 RM – Direct or indirect measurement

Protocols for speed strength Assessment against a spectrum of loads – Performance against > 1 inertial condition – Allows comparison of speed-strength characteristics against varying inertial loads – Decide training needs of each athlete, force-velocity spectrum

Protocols for speed strength Equipment: force platform, linear position transducer Squat jump, countermovement jumps Bench throw: explosively press barbell from chest as faraway as possible – Usually using Smith machine Determine optimal load for average and peak power output – Important in designing power training program – Comparing SJ vs CMJ

Use force platform and force transducer

Interpretation of test results