How Forces Cause Injury
Forces are not only responsible for movement and performance but also play a key role in injury occurrence. In IB Sports, Exercise and Health Science (SEHS), understanding how forces cause injury helps explain why injuries occur, how technique influences risk, and how injuries can be prevented.
Injuries often occur when forces acting on the body exceed the tolerance of tissues such as muscles, tendons, ligaments, or bones.
Types of Forces Involved in Injury
Injuries can result from different types of forces acting on the body.
Common injury-related forces include:
- Impact forces during collisions or falls
- Ground reaction forces during landing
- Tensile forces stretching tissues
- Compressive forces squeezing tissues
In IB SEHS, students should recognise that both internal and external forces can contribute to injury.
Impact Forces and Injury Risk
Impact forces occur when the body collides with another object, surface, or athlete. These forces act over a very short period of time and can be extremely large.
High impact forces can:
- Damage bones and joints
- Tear ligaments or muscles
- Cause concussions or fractures
Examples include tackles in contact sports or hard landings after a jump. In exams, linking impact force size and time to injury risk is essential.
Role of Impulse in Injury Prevention
Impulse plays a major role in determining injury severity. Applying force over a longer time reduces peak force on the body.
This explains why:
- Athletes bend joints when landing
- Gymnasts roll after falling
- Protective equipment absorbs force
Increasing the time over which force is applied reduces injury risk, even if momentum change is the same.
Technique and Force Distribution
Poor technique often increases injury risk by concentrating forces on specific tissues.
Examples include:
- Stiff-legged landings increasing joint stress
- Poor cutting technique increasing knee injury risk
- Incorrect lifting technique increasing spinal load
Good technique spreads forces over larger areas and longer times, reducing stress on individual structures.
Repetitive Forces and Overuse Injuries
Not all injuries are caused by single large forces. Repetitive submaximal forces can also lead to injury over time.
Examples include:
- Stress fractures
- Tendonitis
- Overuse muscle strains
In IB SEHS, students should link repetitive loading and inadequate recovery to chronic injury development.
Exam Relevance for IB SEHS
Injury-related force questions often require applied explanations. High-mark answers clearly describe how force magnitude, direction, and time contribute to injury risk and how technique or equipment can reduce that risk.
Avoid simply stating that “large forces cause injury” without explanation.
RevisionDojo Call to Action
If injury mechanics feel hard to apply in exam answers, RevisionDojo helps IB SEHS students master forces and injury prevention with clear explanations and exam-style practice. It is the most effective way to turn biomechanics knowledge into exam success.
Frequently Asked Questions (FAQs)
How do forces cause injury in sport?
Injuries occur when forces acting on the body exceed the tolerance of tissues or are applied too quickly.
Why does bending joints reduce injury risk?
Bending joints increases the time over which force is applied, reducing peak force on tissues.
How are force-related injuries tested in IB SEHS exams?
Students are often asked to apply force, impulse, and technique concepts to injury scenarios or prevention strategies.
