I found very interesting that the article suggests in more than one point that when the healing is complete, the tissue could be both longer and stronger than before:
“An in vivo study of rat ligament healing
showed a significant increase in tissue ultimate stress (to
80% of control) 2 weeks after a subfailure injury; yet there
was no significant improvement in the tissue laxity over 2
weeks (Provenzano et al., 2002a).
…………….
For instance, examination of
collagen microstructure with scanning electron microscopy
after subfailure damage revealed ruptured collagen fibers
and fibrils, and fiber and fibril dretractionT appeared to have
taken place (Fig. 8). If proteinases are to clear debris and
remove damaged tissue after injury, it is unlikely that the
initial gap between ruptured fibers and/or fibrils would, at
that point, decrease. As such, if the tissue gap is present
when new tissue is dfilled inT, the repaired fiber or fibril
would be longer than its pre-injury length and as such more
lax. (pag. 7)…
The
apparent harmonization of these events provides compelling
evidence that between 3 and 7 days, or at 7 days, the
tissue is undergoing a dramatic remodeling response. In
addition, the strong increase in type I collagen expression,
which is significantly greater than type III expression,
supports the concept of remodeling without significant scar
deposition. These findings distinguish this injury from
pathologies such as tendonitis where inflammation is
known to play a role. Furthermore, this model raises the
likely possibility that fibroblasts within additional tissues
in the body respond in a similar fashion and deposit type I
collagen to repair moderately (i.e. non-clotting and nonscarring)
damaged tissue instead of depositing a type III
fibrotic matrix. (pag 9)”
Now it would be very, very interesting to know what happens after a grade I damage, to understand if, theoretically, would be more efficient, to achieve tissue lenghtening, to cause frequent but very light damage (grade I) or mild damage (grad II) and let it heal.