Introduction to Resistance Training

Endurance training

Perform a muscle contraction at a lower intensity over a prolonged period of time

Isometric exercise requirements

Performed at 60-80% of max capacity 6-10 second contractions 20 reps per day, 6 second hold, near max effort

Power

Rate of performing work that is produced by a muscle per unit of time Related to strength and speed of movement

Volume

Repetitions Sets Frequency

Advantages of Theraband/Theratubing

Resistance varies with color Resistance varies depending on amount of tension on band Inexpensive and easy to use Can target almost any muscle or muscle group

Disadvantages of free weights

Risk of injury at end ranges where surrounding muscles may be actively insufficient or passively insufficient Must be able to control loads using both strength and proprioception

Concentric

Shortening of the muscle Produces tension through ROM Overcomes effect of load Accelerate body segment Max load is less Requires more motor units Uses more energy stores

What variable is most often changed in power training?

Speed

Isometric

Static muscle contraction that does not produce movement of the joint or when a muscle contracts but can not overcome the force that is applied

Why isometric exercise?

Stimulate contraction of very weak muscles Slow/stop atrophy Maintain mobility between muscle fibers Postural muscles contract isometrically

What do you have to have in order to improve power?

Sufficient strength

Specificity of training

Training must mimic the desired functional outcome--type of exercise, velocity, angle of limb, and position of limb

Multiple angle isometrics

Used to increase strength in multiple regions of the ROM Ex- hold at 0, 30, 60, 90, 120

Review fiber types

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Strength training zone

60-100% of 1 RM Most literature refers to working between 60-80% of 1 RM

Endurance

Ability of a muscle to contract repeatedly against a load, generate and sustain tension, and resist fatigue

Strength

Ability of contractile tissue to produce tension and a resultant force based on the demands placed on the muscle

What is resistance exercise?

Any form of active exercise where a dynamic or static muscle contraction is resisted by an outside force

Manual resistance

Applied by therapist throughout the ROM in planes or diagonals Used for specific muscles or groups of muscles Used as progression from active assistive exercise

Overload principle

Body adapts to forces or stresses placed on it by challenging the muscle at a greater level than it is used to performing

Advantages of free weights

Can be done in many different positions Patient must control movement therefore proprioceptors come into play Resistance is easily varied Unilateral or bilateral exercises are possible Usually open chain but can be closed chain

Disadvantages of Theraband/Theratubing

Cannot be specific with amount of resistance Hardest at end range when band is most taut Great for HEP but beware of poor technique, compensation, or substitution Safety

Contraindications for isometric exercise

Cardiac or vascular

Strength training's affect on muscle

Causes an increase in max force producing capacity due to neural adaptations and increases in muscle fiber size

Keys to manual resistance

Challenge patient but don't overpower him/her Apply resistance slowly Stabilize patient!!! Coordinate timing of verbal commands and keep them simple/direct Rest between sets Strength 8-12 reps

Type of contraction and force-velocity relationship

Concentric: increased speed= decreased production Isometric: no speed; more production than concentric Eccentric: increased speed= increased production then level off

Precautions for resistance training

Consider stages of healing High load open chain may have increased risk of injury to unstable joints, recent injuries or surgeries Any situation where closed chain may threaten integrity of bone or ligament

Precautions for isometric exercise

Contract and release gradually Don't hold breath--valsalva maneuver Breath out during contraction

What does the valsalva maneuver do?

Creates increased pressure in the trunk, which stabilizes the trunk and allows one to produce more force for a given movement Causes an extremely rapid rise in BP, followed by a fall in arterial BP

Closed chain exercise

Distal segment is fixed to support surface Weight bearing position Often involves multiple joints

Open chain exercise

Distal segment is free to move in space Non-weight bearing Load is applied to the moving distal segment

Do's and dont's of free weights

Don't--work past fatigue or allow substitution or compensation Do--be aware of posture of patient and proper technique

Free weights

Fixed load that the muscle must overcome Maximally challenges at weakest point in range Can be adjusted by limiting range or varying body position and effect of gravity

Examples of isometric exercises

Hold against a manual force Hold a weight or Theraband in a particular position Hold position against body weight Push or pull an immovable object

Intensity

How much weight is applied during an exercise

What is the goal of resistance exercise?

Improve muscle performance through strength, power, and/or endurance

Power training

Increasing work a muscle must perform in a given amount of time Decreasing the time that a muscle must work to produce a given amount of force

Eccentric

Lengthening of the muscle Tension develops as muscle lengthens Controls effect of load Decelerate body segment (shock absorbency) Max load is greater Aided by non-contractile components Uses less energy stores Requires less motor units to control More likely to result in delayed muscle soreness

Disadvantages of manual resistance training

Load cannot be measured Limited by strength of therapist Speed is slow to moderate Need others for HEP Time intensive for therapist

Characteristics of endurance training

Low intensity High repetitions Prolonged period of time

Load-repetition relationship

Low load- high number of reps High load- low number of reps

Types of concentric/eccentric resistance training

Manual Free weights Mechanical Plyometrics Isokinetics

Types of isometric resistance training

Mechanical or manual

Advantages of manual resistance training

Most effective in early stages when there is weakness Finely graded resistance Works muscle max in all ranges Dynamic or static Resistance and speed are easily adjusted Direct interaction and feedback

Muscle setting exercises

Muscle contracts and produces force but no change in length or motion

What is the least aggressive form of isometric exercise?

Muscle setting

Force-velocity relationship

Muscle shorten and lengthen at different speeds As load increases, speed decreases

Can muscle setting exercises improve strength?

NO, but will reduce atrophy and re-educate muscles on how to properly contract

What change occurs first in resistance training?

Neuromuscular adaptations within muscle itself If demands remain constant, maintenance will occur (aka muscle will change)

Functional strength

Neuromuscular system's ability to produce, reduce, or control forces that are applied during a functional task

Are strength and endurance correlated?

Not necessarily, since a strong muscle may not have adequate endurance for a particular activity

Open chain vs close chain

Open chain may be better for isolation of specific muscle Closed may allow more substitution and stimulate more co-contraction and assist in stability around a joint