Lecture 16 - Biomechanics of Fitness Flashcards
1
Q
what are the 5 goals of physical fitness?
A
- increase muscle strength (force)
- increase muscle power (force and velocity)
- increase flexibility (ROM)
- increase cardiovascular endurance (whole body)
- increase local muscular endurance (part of body)
2
Q
what is resistance training?
A
- application of external loads on parts of the body against which the subject moves
- lifting heavy things –> working against gravity (cables allow you to work against gravity on different planes)
3
Q
what are the 6 ways resistance can be applied to the body?
A
- free weights
- body weight positions
- gravity resistance machines
- variable weights
- isokinetic machines
- programmable machines
4
Q
what are free weights?
A
- dumbbells, barbels, kettle bells, etc.
- simple and inexpensive
- weight is constant throughout the movement
- requires control and stability (so less weight can be lifted in comparison to machines)
5
Q
what muscles are being worked during free weight training?
A
- agonists
- antagonists
- concentric and eccentric muscles
- stabilizers
6
Q
what are gravity resistance machines?
A
- cables
- limit the motion of the weight to only one or two degrees of freedom
- safer than free weights because you don’t need as much control
- remove the need for stabilization
- less likely to have proper form
7
Q
what are variable weight machines?
A
- change the resistance during the range of motion
- ‘even out’ the length-tension curve (more resistance at optimal length, less when muscle is close to insufficiency)
- kidney bean/egg shaped cables to change force through ROM –> changes torque/lever arm
8
Q
what are isokinetic machines?
A
- use an electric motor to force joint motion to occur at a fixed angular speed
- isokinetic dynamometer
9
Q
what are programmable machines?
A
- very common
- on-board computer controls the force and speed of the workout over a length of time
- like an elliptical (can change the resistance etc.)
10
Q
what are the 3 ways you can measure muscle strength?
A
- isometric = muscle stays the same length
- isokinetic = muscle changes length at a constant speed
- isotonic = muscle maintains a constant force
11
Q
how do you measure isometric strength?
A
- measuring the max force produced by a muscle (MVC/ maximum voluntary contraction)
- compared to MIVC (maximum involuntary contraction) which is slightly larger and induced with electrical stimulation (this is painful)
12
Q
how can you measure isokinetic strength?
A
- controlled by an isokinetic dynamometer
- quantify exercise –> ensures compliance
13
Q
how can you measure isotonic strength?
A
- trained with resistance training
- muscles are producing nearly constant force during the rep (weight doesn’t change)
14
Q
what is the goal of muscle power?
A
- to increase both speed and strength (like power lifting)
15
Q
what is muscle endurance? how do you train it?
A
- regulated by the cardiovascular system
- heart and lungs get more effective with training
- local muscle endurance improves as vascularization improves