Growth plates and muscle attachment - why puppies thrive when exercise stress is AGE APPROPRIATE...
"Immature, developing bodies cannot endure excessive amounts of exercise stress without suffering longterm, negative consequences"
Normally a picture is worth a 1000 words - I believe I'll up the ante!
Full disclosure - the tomography pic is from a study using guinea pigs but I think the info is still on point (and the moment I can find the same evidence based study using puppies I'll switch out the link!)
What can we see here? Immature, developing bone lacks the structural integrity (aka: density) needed to withstand multiple stresses from exercise / activity and over-developed muscle (see the blog "#1 and #2 injury factors")
I think a great analogy is concrete - mixed with the correct portions of cement / sand / aggregate and water, it will deliver maximum strength and durability. BUT, if the concrete hasn't been cured long enough before exposing the it to the elements or the pressure of a load, it will break down and jeopardize the entire project.
Concrete is used as the foundation of homes, driveways, roads and bridges. Bones are the foundation of your puppy's body that he will rely upon for his entire life to provide structural attachment for muscles (to create movement) and protect vital organs. Unlike inanimate concrete, bone is a dynamic, living tissue which undergoes remodelling and assists in homeostasis. This is best reason to support your puppy's growth and development - to ensure her body reaches maturity in the best shape possible.
Age Appropriate Exercise/Activity to avoid early onset micro-injuries which have the potential to disrupt optimal bone development
I've created the following illustrations to show how close to the growth plates the major muscle-tendon units are attached
Lets start with the front assembly. The pink highlights the growth plates (large flat bone {scapula / skull / hip bones, etc} have multiple dimensions which utilize a large "sheath" of cell development). The growth plates on long bones (Humerus, Radius Ulna, Femur, etc) are located at the top and bottom - on either side of the joints! Also of note, ball and socket joints have additional growth plates (eg: the femoral head and the hip socket)
SHOULDER STABILZERS:
These large, powerful shoulder muscles can be seen to the side of the bones. They attach (to the scapula) where the red dot is and insert (to the top of the Humerus) where the blue dot is.
When these muscles contract to exert the force necessary to create movement and provide stability, notice all the growth plates they will impact! Imagine the power the Deltoid m. has with 2 points of insertion! Isn't this cool?
SHOULDER FLEXORS:
ELBOW FLEXORS:
ELBOW EXTENSORS:
HIP & THIGH
This is one of my favourite diagrams as it shows how the superficial Gluteal muscle attached to the first few vertebra of the TAIL (changes in direction tail movement is an early indicator of pelvic/hind assembly issues)
GLUTEALS
HAMSTRING GROUP
MEDIAL THIGH:
QUADRICEPS MUSCLE GROUP (4 heads of attachment)
Of special note here - the Patellar Tendon which crosses over the front of the stifle (knee) joint and contains the tiny little Patella
Strong Quad. muscle = strong Quad. tendon = stable knees!
...and everyone's favourite: Iliopsoas muscle. Crucial for strong CORE (notice the attachment along the lower spine)
The slides are from a presentation which can be seen by following this link : https://www.youtube.com/watch?v=hT4ObtdTc6s