Hey Bruno,
In addition to Rebecca’s already thorough reply:
Research has shown gelatine [or collagen] can help promote bone growth, increase collagen production, thickened cartilage and potentially decrease joint pain
Also vitamin C rich foods are important for injury repair
The following describes some very interesting research from Keith Baar et al, into the efficacy of combining gelatine and vitamin C supplementation, with tendon loading exercise, to improve strength, prevent injury, and – when necessary – speed recovery:
Exactly which exercise(s) you chose to implement the loading protocol would depend on where you see deficit(s). But for you – lower leg issues – jump rope as per article, is ideal.