Force Summation

1. Force Summation By Amanda, Georgia & Jazmin

2. Definition • When trying to give much momentum to an object or body as possible, force summation becomes important. The amount of momentum that we can give to an object is determined by the sum of all the forces generated by different body parts.

3. The combination of forces produced by different parts of the body. Many body parts come together to maximise the force.

4. For example in shot-put • When starting to throw a shot-put you use a sequences of body segments. Starting from the biggest muscles, you use quadriceps and hamstrings then move on to abdomens and finally to the smaller faster muscles, biceps and triceps. • This creates a full range of movement and maximum force.

5. http://www.youtube.com/watch?v=mXtOphTocJ8

6. Answers to Pg. 75 and 76 • 1a legs – hips – trunk – shoulders – arms – wrist – javelin • 1b there would be unco-ordinated movement and a loss of force being generated • 1c by generating large amounts of momentum in large muscle groups, this can be passed to a smaller body part. It must move much faster because it is lighter for total momentum to stay the same. • 2a we cannot generate enough force

7. 2b Bring the arm back just enough to get maximum force at the start of the throw • 2c Force transfer is legs – hips – trunk – shoulder – arms – hand – ball. • 3 It means the longest possible lever can have a longer path to travel meaning it can generate greater velocities.

8. Summary • The player bends the kicking leg enough so quadriceps can generate large forces when it contracts. The forces generated start at the hip/trunk – thigh – lower leg – foot – ball. By drawing the leg back (extent ion) they get full range of motion of the foot on contact. Bending the kicking leg also decreases in inertia meaning it can generate more angular velocity.