Biomechanics

Biomechanics

The mechanisms through which musculoskeletal components interact to create movement.

Skeletal musculature

A system of muscle that enables the skeleton to move.

Origin

The proximal attachment of a muscle.

Insertion

The distal attachment of a muscle.

Fleshy attachment

Occurs at the origin, where muscle fibers directly affix to the bone.

Fibrous attachments

The muscle blends into and with muscle sheaths (tendon).

Agonist

The muscle most directly involved in bringing about a movement, also known as the prime mover.

Antagonist

The muscle that acts opposite to the agonist; it can slow or stop a movement and assists in joint stabilization.

Synergists

Muscles that aid directly in the movement.

Fulcrum

The pivot point of a lever.

Moment arm

The perpendicular distance from the line of action to the fulcrum.

Mechanical advantage

The ratio between the moment arm of applied force (muscle force) to the moment arm of resistance force.

First class lever

A lever where muscle and resistive force are on opposite sides of the fulcrum.

Second class lever

A lever where both muscle and resistive force act on the same side of the fulcrum, with the moment arm of muscle greater than that of resistance.

Third class lever

A lever where both forces act on the same side of the fulcrum and the moment arm of resistance is greater than that of muscle.

Strength

The capacity to exert force at any velocity.

Power

Explosive strength; can be calculated as force x velocity or work divided by time.

Negative work

Force exerted in the opposite direction of weight movement.

Neural control

The impact on maximum force output by recruitment of motor unit number and size.

Muscle length at rest

Actin and myosin filaments lie next to each other, leading to the greatest force potential.

Isometric contraction

Contractile force equals resistive force; there is no change in muscle length.

Sources of resistance

Factors like gravity, inertia, friction, fluid resistance, and elasticity that provide resistive force during movement.

Back injury concerns

Back injuries are likely due to disk herniations and the vulnerability of the spine; proper alignment and technique are crucial.

Valsalva maneuver

Forcing expiration against the glottis, which increases internal pressure and supports the vertebral column but can have negative side effects.

Weight lifting belt

Used for support during weight lifting but may not stabilize core muscles effectively.

Torque

A measure of the force that can cause an object to rotate about an axis.

Kinematics

The study of motion without considering the forces that cause it.

Kinetics

The study of the forces that cause motion.

Center of mass

The point at which the mass of an object is concentrated and about which it balances.

Inertia

The tendency of an object to resist changes in its state of motion.

Balance

The ability to maintain the center of mass over the base of support.

Proprioception

The sense of body position and movement, allowing the body to adapt to its environment.

Elasticity

The ability of a material to return to its original shape after deformation.

Viscosity

A measure of a fluid's resistance to deformation or flow.

Power training

Exercise programs designed to improve explosive strength and power output.

Maximal strength training

Programs focused on increasing the maximum amount of force that can be exerted.

Muscle hypertrophy

The increase in muscle size through strength training.

Aerobic capacity

The maximum amount of oxygen the body can utilize during intense exercise.

Anaerobic threshold

The point at which the body starts to accumulate lactic acid in the muscles.

Principle of specificity

The training principle stating that adaptations are specific to the type of training performed.

Overtraining syndrome

A condition resulting from excessive training without adequate recovery.

Circuit training

A form of body conditioning or resistance training using high-intensity efforts for a specific duration.

Recovery

The process of returning to a normal state after physical exertion.

Endurance training

Activities aimed at improving the body's ability to sustain prolonged exercise.

Muscle recruitment

The activation of additional motor units to increase force output.

Stretch reflex

An automatic response by muscles to prevent overstretching.

Joint stability

The ability of a joint to maintain its position and alignment during movement.

Biomechanical efficiency

The optimal use of body mechanics to maximize performance and minimize injury.

Functional training

Exercise that mimics everyday actions and movements.

Speed-endurance training

Training aimed at maintaining high speeds for prolonged periods.

Psychological aspects of performance

Mental factors that influence athletic performance, such as focus and motivation.

Health-related fitness components

Aspects of fitness that enhance health, including cardiovascular endurance, muscular strength, flexibility, and body composition.