Response to a MJ Body Weight Exercise article

The other day, I posted how much I hated an Men's Journal article about using body weight exercises... I received a bunch of replies regarding my comments, so thought I would create a video response to clarify what my issues are with the article.

Summary:

1. The article was written as a "hype" piece with ridiculous statements about the benefits of "body weight exercises" and the downfalls, even the dangers of "weighted exercises".
2. "Body Weight Exericses" are just exercises that use your body weight as resistance or load rather than some other form of weight...  a body weight squat is NO different from a barbell squat except for the resistance or load.
3. "Body Weight Exericses" are great and can be a useful part of a "complete" training regime.
4. DON'T BELIEVE THE HYPE!!!  ... in other words, do your research and be an educated consumer... a magazine's primary goal is selling advertisement space, second is selling magazines, last is credible information.... keep in mind good information is BORING.

Arms trapped - visual swing fault

A very common "visual" swing fault is the arms being stuck to the body or pinned to the torso and not properly releasing into impact. This video explores the cause of the issue on a biomechanics or sequence/coordination level and how to approach resolving the swing fault.

The swing fault is almost always mis-diagnosed as the body moving too fast for the arms as a result the remedy revolves around the body - hips/torso being too fast and the arms being too slow. 

In fact the issue is almost always the arms being too fast or too quick to accelerate.  The arms initiate the downswing rather than the lower body and disrupt the kinetic link sequence.  The torso then accelerates late in the swing, out of sequence, giving the appearance of the arms being trapped behind the body. 

The ZenoLink 3D "speed trap"

An explanation of how ZenoLink uses video to create a 3D representation of bodies or objects in space and from that data calculate SPEED ! resultant speed as well as the direction of applied speed

some related links

Velocity
Derivative
Direct Linear Transformation (DLT)
DLT Method

Ground Reaction Forces Applied for Golf Swing - Center Of Pressure

This video is an overview description of pressure and center of pressure measurements in the golf swing, followed by an explanation of entry level training of foot to ground interaction in the golf swing:

Center of Pressure between the two feet is influenced by not only the amount of force applied through the foot into the ground by to a large extent the direction of the applied force.  Keeping a good foot-ground interface through out back swing, transition and down swing is important for creating good force and a good pattern of force application.

some related research:

Pressure - Wikipedia
Center of Pressure - Wikipedia
Plantar Center of Pressure and it’s Effect on Golf Swing Distance and Accuracy
An Analysis Of The Kinetics And Kinematics Of The Golf Swing
Biomechanics of shoe-ground interaction in golf

Are back-off sets useful after a strength workout?

great research summary on using a "back-off set" after a strength workout

Are back-off sets useful after a strength workout?

"The researchers concluded that the combined 4-week training program led to a larger increase in 1RM leg press than the simple 4-week strength program followed by the normal group. The only difference between the two programs was the addition of a single set at 50% of 1RM after the main sets."


"What are the practical implications? For strength and power athletes: Adding a back-off set at 50% of 1RM following a workout involving a strength protocol at high percentages of 1RM (e.g. 85 – 90%) may increase strength and size gains without compromising gains in power."


... I will definitely be adding a back-off set to see if it impacts my strength building protocols...

ground reaction forces in golf: a response

if you try to create a rotational movement like a med ball pass standing on a slippery surface, why do your feet move in the opposite direction of the intended rotation??

you use ground reaction force to produce a force-couple/torque which is translated from the feet-ground through the legs to the pelvis to initiate the rotational motion which in turn produces the subsequent coordination to toss the med ball

ground reaction force is the force that is equal and OPPOSITE of the force applied by you into the ground through your feet

when you stand on "sliders" you aren't able to create friction, so the ground is not able to "push back" ... the legs twist in the direction you are applying force

this video/response is in response to a nice video post last week by James Hong to Michael Beaumont regarding the lower body action or mechanism in the golf swing

Some papers on the topic... use the references in each paper as additional resources and/or pubmed or google educational searches on ground reaction forces in swing patterns or in sport biomechanics - also try to google "cavanagh ground reaction forces":

Lower Body Mechanics During the Baseball Swing
 
Ground Reaction Forces and Torques of Professional and Amateur Golfers

A comparison of golf shoe designs highlights greater ground reaction forces with shorter irons

Messier, 1985

Williams and Cavanagh, 1983

a starting point

If you are going to discuss biomechanics you should have some basic idea of the terms, concepts, definitions, units of measurement, principles, etc.

This is a good reference... not the only one, but a good start:

Glossary of Biomechanical Terms, Concepts, and Units 
Mary M Rodgers and Peter R Cavanagh
PHYS THER. 1984; 64:1886-1902.