http://www.theverticalsummit.com/viewtopic.php?t=1102

In the upward phase of the VJ, we have:

A. Lower body
hip extention
knee extention
plantar flexion.

B. Back:
Retroflexion

C. Shoulders:
anteflexion

Before i start, might be usefull for some people:
* glutes = gluteus maximus + gluteus minimus + gluteus medius
* hamstrings = semitendinosus + semimembranosus + biceps femoris
* quads = musculi vasti + rectus femoris
musculi vasti are the part that only do knee extention, while rectus femoris can do a hip flexion too
* Calves = gastrocnemius. There are other muscles that also do a plantar flexion though, but no muscles that do both knee flexion and planter flexion

Muscles involved in each movement: (quoted from my book of anatomy, not making it up)
(according to Van Lanz)

A.1 hip extention
- Gluteus maximus : 45%
- Gluteus medius : 8%

- Semitendinosus : 4%
- Semimembranosus : 13%
- Biceps femoris (caput longum) : 4%

- Adductor magnus : 16%

A.2 knee extention
- Rectus femoris : 16%
- Musculi vasti : 83%

A.3 Plantar flexion
- Tibialis posterior : 2%
- Flexor digitorum longus : 2%
- Flexor hallucis longis : 5%

- Gastrocnemius : 48%
- Soleus : 39%
- Plantaris : (no number added)

- Peroneus longus : 2%
- Peroneus brevis : 2%

B. Back retroflexion
Unfortunately this is not in my book.
I have the muscles involved in the movement though:

- serratus posterior superior
- serratus posterior inferior
- splenius capitis and cervicis
- erector spinae
- spinalis
- semispinalis
- multifidus
- rotares
- intertransversii
- interspinales

C. Shoulders anteflexion:
- deltoideus (front fibers: 41%
- pectoralis major : 16.2 %
- biceps (caput breve) : 12.7 %
- supraspinatus : 4.4 %
- coracobrachialis : 8.4 %
- infraspinatus : 4.4 %
- subscapularis : 3 %

OVERALL RESULTS:

first of all i define a posterior chain as the muscles that are on the backside of your body, this meaning the upper back, lower back, glutes, hams and lower legs.

in the upward phase only:

hip extention :
PC : 84%, AC : 0% (adductor magnus : 14%)

knee extention:
PC : 0%, AC : 100%

plantar flexion:
PC : 100%, AC: 0%

back retroflexion :
PC : 100%, AC : 0%

shoulders anteflexion :
PC : 8.8%, AC : 91.2 %

OVERALL CONCLUSION AND NOTES

- These numbers dont say a lot since they are relative. What im trying to say is that i dont have any numbers on e.g. how important knee extention is compared to hip extention.
- Also, it is important that a strong antagonist is needed, so that the muscle can contract to its full potential.
- this is all voluntary contraction. Not taken into account is unvoluntary contraction = reactive ability.
_________________
current stats/goals by end of summer:
6ft
around 160 lbs / 170
almost 19
SV : 28-29 / 30-31
RV 2 : 30-32 / 33-34
RV 1 : 33-34 / 37-38

Believe in yourself

thanks greg