060617 Mechanical load consists of the following:
Magnitude of force
Magnitude of the load density or the intensity of the load will generally be above eighty to ninety percent one to ten repetition maximum in order to see improvements in the tissue response.
Speed of force development
The rate or speed of loading means how fast the force is being applied to move the load in a concentric muscle contraction (force applied against a weight with the muscles shortening). Think speed during the lift.
The direction of forces
Varying the direction and pattern of movement will stress the bone and the attaching musculature. Full range of motion in all exercises ensures to a certain extent that the forces are applied as required.
Volume of force applied
The first three mentioned above are primarily responsible for bone mineral improvements. Typically the repetitions do not need to exceed thirty to thirty five to see improvements IF the load is within the correct intensity zone (80%-90% 1-10RM).
Exercise prescriptions for bone growth stimulation*
- Volume 10 reps for 3-6 sets
2. Load 1-10 RM at 80%-90%
3. Rest 1-4 minutes between sets
4. Variation Undulating periodization patterns
5. Exercise selection Structural, multi-joint, large muscle groups
*Essentials of Strength Training and Conditioning
Baechle, T. R., Earle, R.W. Human Kinetics 2001
The greater the magnitude or intensity, the higher and faster the power output, and the direction of force all contribute to the successful laying down of new bone growth.