Is the phrase "an extensive amount of hard work" correct and does is sound natural?

Question

What I want to indicate in my writing is that I understand I need to work really hard as a student in the program. I'm using this sentence:

I am aware that studying in such an intense and demanding program requires an extensive amount of hard work and dedication.

My question is, is the phrase "an extensive amount of hard work" correctly used? and if so, does it sound natural? is there a better alternative?

I am trying not to use words like "great" and "huge" too often in my writing that is why I used "extensive".

Answer 1

That doesn’t sound quite right. “Extensive” carries with it connotations of length, depth or detail. It does not simply mean “large”.

Perhaps “a considerable amount of hard work”?