"I feel I am improving everyday and my bowling is getting better all the time and in every match. It has been a good comeback for me since returning to the team last year," Asif said.
The pacer told a television channel that he had vowed to give his best when he returned to the team.
"Being banned for 12 months and facing other problems in this period was a big test for me. My cricket suffered a lot and it took a lot of effort physically and mentally to come back to international cricket," Asif said.
The lanky pacer finished with 5 for 77 including a spell of 4 for 12 runs on the second day of the first Test against England at Nottingham leaving him just one wicket short of the 100 mark in Test matches.
Asif returned to the national team last year in September in the Champions Trophy after completing his 12-month suspension period for flunking a dope test during the Indian Premier League.
He also had to spend 19 days in detention in Dubai for possession of a banned substance in 2008 while returning from India to Pakistan.
His personal life was also in tatters until recently when a well-known actress Veena Malik accused him of not returning her millions of rupees he took from her during his suspension from cricket.
But Asif said he was now over these issues and concentrating on his bowling.
"I think having a bowling coach like Waqar Younis has helped a lot and allowed me to slowly come back. But as a bowler also I feel I am improving in every match and the rhythm is good," he said.