Resistance Training

Question 1

Types of Resistance

Answer 1

Gravity
Inertia (Resistance to change)
Friction
Fluid
Elastic
Electronically controlled

Question 2

Gravity

Answer 2

• F=ma so w=mg
• Resistance arm not constant throughout the ROM with free weights
• Implications
  – Alter limb and/or resistance training position.
  – There is likely always a “sticking point” somewhere in the ROM with free weight use. (Our maximal weight lifted during our 1 repetition maximum is the maximum at the “weakest” point in the ROM!)
  – Specificity of Training! Is the greatest resistance always the goal? We train differently for strength vs. power

Can’t always start in specificity but want to build to it!!!

Question 3

Free Weight Using Gravitational Resistance - Advantages

Answer 3

• Variety of exercises
• Potential for specificity of training

Question 4

Weight Stack Machine Using Gravitational Resistance - Advantages

Answer 4

• Safety, less skill
• Provide resistance that may be difficult to provide using free weights

Question 5

Nautilus/Cybex Weight Stack Machines Using Gravitational Resistance - Advantages

Answer 5

• Alter moment arms (motive & resistive)
• Match torque capability of individuals (Match internal and external torque to get rid of sticking point) - Don’t always work.

Question 6

FA > RA

Answer 6

Smaller resistance moment

Question 7

FA < RA

Answer 7

Larger resistance moment

Question 8

Does the internal and external match?

Answer 8

Very hard in the beginning, much easier the more degrees

Question 9

Ineria

Answer 9

• Resistance to change in linear/angular motion
• Acceleration/deceleration of the limb & weight stack, using “body blade” or “shake weight” (Concentric/Eccentric)
  – Specificity – Power
  – Start of movement (concentric) - resistance, end of movement (eccentric) - loading; Purpose is for deceleration on RC muscle with baseball players.
  – When using free weights and you reach the sticking point, you use angular momentum to compensate.

Question 10

Friction

Answer 10

Limiting Friction: Point of Hightest Resistance
Limiting is higher than dynamic friction.
Ex: Bike Pedal

Question 11

Fluid

Answer 11

Body segment(s) moving through a fluid or just a fluid moving through a hole
Hydraulic (liquid) or pneumatic (air).
Resistance Force: F = k * V
Ex: Water: has a certain k, tell someone to go faster you increase the resistance force and muscle force production is down makes it very difficult.
Does not make force-velocity relationship

Question 12

Elasticity

Answer 12

Resistance Force: k * X (k is constant due to the characteristics of the elastic material, X is the distance stretched; increasing X, increases force)
Angular component based on lever!
Tricep Kickback: No moment arm in the beginning of the movement to activate the triceps in the beginning, going throughout the movement activates triceps.

Question 13

Theraband - k constant

Answer 13

Can get similar forces depending on the colors. Folding doubles the constant. Pulling it farther apart generates more force. Band looses 8-12% of resistance after 500 cycles.

Question 14

Electronically

Answer 14

• Motor, pump, electromagnetic resistance
• Angular velocity nearly constant, resistance torque matches limb torque
• Implications?