Mechanical Advantage

Different types of lever have different types of mechanical advantage. Short effort arms can make rapid movements and can make a range of movements. Short resistance arms can move heavy weights. The type of mechanical advantage depends on:

Distance between effort and fulcrum

The distance between the effort (muscle) and the fulcrum (joint). This distance is called the effort arm.
Mechanical advantage = effort arm divided by (÷) the resistance arm.

Distance between resistance and fulcrum

The distance between the resistance (load that needs moving) and the fulcrum (joint).
This distance is called the resistance arm.
Mechanical advantage = effort arm divided by (÷) the resistance arm.

First and Third Class Levers

First and third class levers have an effort arm that is shorter than the resistance arm. For first and third class levers, the effort arm ÷ resistance arm is less than 1.

Third class lever - elbow

When flexion (bending) happens at the elbow, the effort arm is the distance from the biceps (effort) and the elbow joint (fulcrum), which is very short.
The resistance arm is the distance from the hand (resistance) to the elbow joint (fulcrum), which is very long. This means that the hand can move quickly with a wide range of movement.

Second Class Lever

The second class lever system is ideal for lifting weights. This is why we see it in the ankle, where it carries the weight of the body.

Second class lever - ankle

Here, the effort is further away from the fulcrum than the resistance (effort arm longer than the resistance arm).
When plantar flexion happens at the ankle, the effort arm is the distance from the gastrocnemius (effort) to the ball of the foot (fulcrum), which is long.
The resistance arm is the distance from the body weight (resistance through the middle) to the ball of the foot (fulcrum), which is very short. This means that the range of movement is not too large but that it can support a heavy weight.

1Applied Anatomy & Physiology

1.1The Musculoskeletal System

1.1.1Musculoskeletal Structure

1.1.2Structure of the Skeleton

1.1.3Functions of the Skeleton

1.1.4Joints

1.1.5Joints 2

1.1.6Antagonistic Muscle Movement

1.1.7End of Topic Test - The Musculoskeletal System

1.1.8Exam-Style Questions - Musculoskeletal System

1.2The Cardio-Respiratory System

1.2.1Pathway of Air

1.2.2Blood Vessels

1.2.3Blood Vessels 2

1.2.4Structure of the Heart

1.2.5Cardiac Cycle

1.2.6Measures of Heart Performance

1.2.7The Mechanics of Breathing

1.2.8The Mechanics of Breathing 2

1.2.9The Lungs

1.2.10End of Topic Test - The Cardio-Respiratory System

1.2.11Exam-Style Questions - Cardio-Respiratory System

1.3Anaerobic & Aerobic Exercise

1.3.1Aerobic & Anaerobic Respiration

1.3.2Recovering After Exercise

1.3.3Treatments for Recovery

1.4Short-Term Effects of Exercise

1.4.1Short-Term Effects of Exercise

1.4.2Long-Term Effects of Exercise

2Movement Analysis

2.1Lever Systems

2.1.1Lever Systems

2.1.2Mechanical Advantage

2.1.3Basic Sporting Movements

2.1.4Basic Sporting Movements 2

2.2Planes & Axes of Movement

2.2.1Planes & Axes of Movement

2.2.2End of Topic Test - Movement Analysis

2.2.3Exam-Style Questions - Movement

3Physical Training

3.1Health & Fitness

3.1.1Health & Fitness

3.2The Components of Fitness

3.2.1The Components of Fitness

3.2.2Sports & Fitness

3.2.3Fitness Testing

3.2.4Measuring Agility & Balance

3.2.5Measuring Cardiovascular & Coordination

3.2.6Measuring Endurance & Power

3.2.7Measuring Reaction Time & Strength

3.2.8Measuring Strength, Speed & Flexibility

3.2.9End of Topic Test - The Components of Fitness

3.2.10Exam-Style Questions - Fitness Tests

4The Principles of Training

4.1Principles of Training

4.1.1Principles & Circuit Training

4.1.2Continuous & Fartlek Training

4.1.3Plyometric & Static Training

4.1.4Weight & Interval Training

4.2Optimising Training

4.2.1Optimising Training

4.2.2Altitude & Seasonal Training

4.2.3Warming Up

4.2.4Cooling Down

4.2.5End of Topic Test - Principles & Optimisation

4.2.6Exam-Style Questions - Sport-Specific Fitness

5Using Data

5.1Types of Data

5.1.1Quantitative Data

5.1.2Qualitative Data

5.2Data Presentation & Analysis

5.2.1Data Presentation & Analysis

6Sports Psychology

6.1Skills

6.1.1Skills

6.1.2Skills 2

6.1.3Goals & Targets

6.1.4Skills HyperLearning

6.2Feedback & Preparation

6.2.1Information Processing

6.2.2Guidance

6.2.3Guidance 2

6.2.4Feedback

6.2.5Mental Preparation

6.2.6Controlling & Optimising Arousal

6.2.7Exam-Style Questions - Skills & Guidance

6.3Personality & Behaviour

6.3.1Aggression

6.3.2Motivation

6.3.3Personality Types

6.3.4End of Topic Test - Sports Psychology

6.3.5Exam-Style Questions - Aggression & Motivation

7Socio-cultural Influences

8Health & Fitness

8.1Overview of Health

8.1.1Well-Being & Fitness

8.1.2Types of Health

8.2Sedentary Lifestyles

8.2.1Sedentary Lifestyle

8.2.2Obesity & Performance

8.2.3Somatotypes

8.3Nutrition & Hydration

8.3.1Nutrition

8.3.2Nutrition 2

8.3.3Hydration

8.3.4End of Topic Test - Health & Fitness

8.3.5Exam-Style Questions - Nutrition & Hydration

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