What’s making tennis players get better later and stay better when players from a decade ago were already retired?
No doubts, it’s a question with multiple answers.
Added power? Training method? Diet? Recovery? Just a cycle in tennis?

No doubt there is a mental side of this change too …

Here are the numbers:
MEN
in 1992 the average age of men’s TOP 10 was 23.2 years
in 2002 it was 24.5 years.
in 2015 it was 28.6 years.
in 24 years, from 23 years to 28.5 years – 5 years difference.
– In the top 10, only 1 player is younger than the average age from 13 years ago.
– There have been 10 teenage Grand Slam winners (with multiple winners as Becker and Wilander).
Now only 4 teenagers in the top 100.
– In 1995 the highest ranked 32-year old man was No 124, and only 8 men of that age ranked in the top 500.
Now, 18 players that old are ranked higher than 124, including 5 in the top 25!
– The last teenager to win a Grand Slam was Nadal who turned 19 while winning the 2005 French Open.

WOMEN
In 1992 the average age of the women’s top 10 was 21.7 years.
In 2002 it was 22 years.
In 2014 it was 25.9 years – same difference than men (+5 years in 24 years)
– In 1990, 20 women in the top 30 were under 23 years old. Now only 6.
– 8 women had won Grand Slams before turning 19. Now, only 1 such teenager ranked in the entire top 150.
– Now: 15 women over 30 in the top 100. In 2000, there were only 2.
– In 2012 – only 4 years ago, there were 3 women over 32 in the top 100. Now: 8 women over 32.

MEN – TOP 100 – August 2016
Only 1 teenager!
10% under 23 years
1/3 over 30 years
Not yet 18: 0
Not yet 19: 1 (Taylor Fritz)
Not yet 20: 3 (Zverev, Coric, Fritz)
Not yet 21: 5 (Zverev, Coric, Fritz, NIshioka, Khachanov)
Not yet 22: 7 (Kyrgios, Zverev, Coric, Fritz, Edmund, Nishioka, Khachanov)
Not yet 23: 11 (Thiem, Kyrgios, Zverev, Rouille, Coric, Fritz, Edmund, NIshioka, Thompson, Khachanov, Monteiro)

At least 33: 15
At least 32: 20
At least 31: 27
At least 30: 34 (33%)