Last WeekProgressive resistance – gradually increase the

workload (sets, reps, weight, intensity, etc.) to avoid muscle adaption and plateau.

Focus on 2-3 muscle groups per workout.

Multi-joint and multi-muscle group exercises – deadlifts, squats, pull-ups, push-ups, etc.

Muscle Contractions

Objective this weekDifferentiate between various types of muscle

contractions.

Apply your knowledge of muscle contractions to analyze specific exercises.

Opposing muscles contract and relax

Opposing muscles contract and relax

Which muscle is contracting?

Which muscle is contracting?

Types of muscle contractionsIsometric – joint angle and muscle length do

not change during contraction (static position).

Isotonic – tension remains unchanged but muscle length changes (lifting a weight through a range of motion).

Isometric Exercises

Isometric Exercises

Any other isometric exercises?

Brainstorm with your elbow partner.

Isometric Exercises

Isotonic ContractionsConcentric contractions – muscle contraction in

which the muscle shortens while generating force.Example: upward phase of a biceps curl (from

bottom to top).

Eccentric contractions – the muscle elongates while under tension due to an opposing force.Example: lowering phase of a biceps curl (from top

to bottom).

Concentric vs. Eccentric(positive vs. negative)

Which is concentric and eccentric?

Which is concentric and eccentric?

More on eccentric contractionsGreat for hypertrophy (increasing muscle size).

Cause greater microscopic tears in muscle fibers and thus provide the stimulus to make your muscles grow and strengthen.

Lower the weight slowly, maybe use a 4-5 seconds count.

Work with a partner so you can increase the weight.

Don’t go overboard. Longer recovery time Risk of overtraining

Collaborative WorkGroups of 3 to 4

Select one exercise and demonstrate the concentric and eccentric phases

Identify the muscles being worked

Identify the movementFlexion/extensionAbduction/adductionSupination/pronationRotation