Questions & Answers about ככל שאני מתרגלת בתדירות גבוהה יותר, כך הניידות שלי משתפרת.
It is a very common Hebrew pattern meaning the more ..., the more ... or the more ..., the better ....
So here:
- ככל שאני מתרגלת בתדירות גבוהה יותר = the more frequently I practice
- כך הניידות שלי משתפרת = the more my mobility improves / my mobility improves accordingly
In other words, it expresses a relationship between two changing things.
In Hebrew present tense, the verb usually does not show person clearly the way English does. It mainly shows gender and number.
So מתרגלת tells you the subject is feminine singular, but by itself it could mean something like:
- I practice (if the speaker is female)
- you practice (addressing one female)
- she practices
That is why אני is needed here: it makes it clear that the subject is I.