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Download Principles of Muscular Strength and Endurance
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Principles of Muscular Strength and Endurance Types of Muscles Skeletal Smooth Lines blood vessels, hollow organs Cardiac Found only in the heart Muscular Strength Strength: maximal force a muscle can generate for a single maximal effort 1-RM (repetition max) measures muscle strength If you want stronger, more powerful muscles then your goal should be strength not endurance Muscular Endurance Represents the ability of a muscle to generate a sub-maximal force repeatedly over time If this is your goal then endurance training is what you need Benefits of Resistive Training Inc mm strength Inc mm endurance Hypertrophy Inc flex and ROM Inc lean body mass Dec body fat Inc basal metabolism Inc performance Maintenance of indep living Improved phys appearance Prevention of osteoporosis Inc CR fitness Dec BP Overload Gradual increase in frequency, duration, and intensity Goal: recruit or stimulate more muscle tissue Long-term adaptation: mm hypertrophy Increase in mm cell size as a result of increased protein synthesis (hyperplasia) The bigger the mm the more force it can produce Principle of Specificity The body will only adapt specifically to the type and nature of exercise training that are encountered How the body adapts and improves is related to how hard and in what manner it is trained Speed, contraction type, mm groups Detraining Principle of reversibility MM tissue will not retain any gains if training is discontinued or reduced Atrophy Reduction in mm size Types of Contractions Isometric Concentric Eccentric Isometric Contraction No change in mm length (static contraction) No joint ROM Concentric Contraction Dynamic shortens movement in which the mm Eccentric Contraction Dynamic movement in which the mm lengthens Usually occur after the mm has been in a shortened state Skeletal Muscle Actions Static Movement: no joint movement Involve maximal or submaximal mm contraction EX: Quad sets post ACL surgery Dynamic Movement: changes in mm length and joint movement Resistance training Types of Skeletal Muscle Fibers Slow twitch (Type I) Fast twitch (Type II) Fast-oxidative-glycolytic Fast-glycolytic (Type IIb) (Type IIa) Slow Twitch (Type I) Low intensity, long duration Aerobic High endurance and fatigue resistant Running/cycling rely on Type I fibers Postural mm are Type I Fast Twitch (Type IIa and Type IIb) Rapid forces Capable of shortening and developing tension 3-5 times faster than slow twitch Anaerobic, have limited aerobic power Fatigue rapidly Type IIa fibers have greater anaerobic capacity than Type I, Type IIb more than Type IIa Factors Effecting MM Strength and Endurance Muscle size Larger the cross section area, the stronger the muscle Strength training does not increase the strength of contraction, but increases the size of the mm cell Gender: Females low testosterone level Age Use it or lose it Loss of strength 1%/year after 25 yo Isometric Training Increases strength at a given joint angle No joint movement Must Used work a variety of joint angles primarily in rehab Precautions: hypertension (valsalva effect); indiv presenting coronary risk Isotonic Training Most common method of strength training “Progressive resistive exercise” Overload principle Constant resistance Variable speed of mm contraction Free weights, machines Works full ROM Isokinetic Training Speed remains constant; weight varies Used for rehabilitation Equipment very expensive (Cybex: $45,000) Determining Amount of Resistance 1 RM Trial and error Delorme (10 RM) 1 Repetition Maximum Determine 1 RM Take 60% of that value and begin with that amount of resistance 60% will develop strength, but mostly endurance The closer you work to your 1 RM, the greater the strength gains and the risk of injury Trial and Error Determine an amount of resistance you can lift 8 to 12 times Delorme 10 RM Complete 3 sets 1st set: 50% of 10 RM 2nd set: 75% of 10 RM 3rd set: 100% of 10 RM Guidelines for Resistance Training Warm-up Adjust equipment Exercise large muscle groups first Begin any resistive program slowly and with lower intensities Overload Guidelines Cont. Strengthen Work your weak side both arms and legs Isolate muscle groups Protect the back Total body workout 2-3 times per week Alternate days Alternate equipment Guidelines Cont. Maintenance 2 sets, twice/week OR 1 set of 12 reps Reassess periodically Free Weights Use a spotter Inc chance of injury Lack of stability May build strength faster Wt increments are easily changed Weight Machines Weight increments usually 5, 10 lbs The machine controls line of force Offers stability Fewer injuries No spotter required What is your goal? To gain some strength and some endurance? To build primarily strength? To build primarily endurance? To develop great hypertrophy? As you develop strength, you will develop some endurance and vice versa Identify your goal Some strength and some endurance? 8-12 reps (60% of 1 RM) Primarily Fewer than 8 reps (80%-90% of 1 RM) Primarily More RM) strength? endurance? than 12-15 reps (60% or less of 1 Hypertrophy? 50 lbs x 20 reps x 3 sets = 3000 lbs 100 lbs x 6 reps x 3 sets = 1800 lbs Which workout should you use? Muscle Soreness Results from structural damage Desirable to have small, microscopic tears How to avoid mm soreness: Stretch, minimize eccentrics, minimize isometrics, use low intensities, progress slowly Tips Never hold your breath while exerting force when weight lifting Valsalva Exhale effect or maneuver as you apply force Inhale as you recover Other Strength Training Techniques Circuit Training Plyometrics Calisthenics Circuit Training Uses a series of 12 to 15 stations Rotate through circuit 3 times Consists of Weight training Calisthenics Brief aerobic exercise Plyometrics Develops mm explosiveness and forcefulness Consists of an eccentric contraction followed by a concentric contraction Involves hops, bounds, depth jumping, medicine ball, etc. High probability of injury Muscle Dysmorphia Reverse anorexia Feeling of being small or weak Males more common Supplements/steroid use Excessive weight training Anabolic Steroids Synthetic forms of testosterone MM hypertrophy Drug type and amount Duration of drug usage Amount of wt training Female Side Effects Hypertension Fluid retention Decreased breast size Facial and body hair Deeper voice Male Side Effects Liver dysfunction Reduced testicular function Loss of sexual interest Headaches, nausea, acne Unpredictable aggressive behavior Increased risk of coronary heart disease Increased risk of kidney tumors Where can I get them? Easily obtained Mail order Illegal channels Local gyms Athletes Physicians How to mask steroid use? A science of its own Calisthenics The body and its extremities provide resistance Used in aerobic dance routines EX: crunches and push-ups Suited to supplement strength training Good for beginners Bench Press 1. Lie on a flat bench with eyes directly under the bar. 2. Keep feet flat on the floor with hands spaced evenly slightly wider than shoulder width. 3. Lift bar off the racks and slowly lower the bar to the highest point on chest. 4. Drive the bar upwards and back over the eyes to arms length while exhaling. Leg Press Push Ups and Crunches
