The Frenchman believes that the improved standard of training pitches has resulted in the deterioration in the quality of challenges in football.
"I feel tackling is a technique," he told Arsenal's official website. "You look at a training ground 20 years ago and today. There are two main differences - tackling disappearance and quality of the heading disappearing.
"If you take the number of good headers in every team 25 years ago and compare them to today, there is no comparison. I've seen training sessions 20 to 25 years ago where you had to lift the ball to train.
"You could not play on the ground. Today, every training ground is immaculate. What's happening? You have no tackling and no heading."
Arsenal are currently sixth in the Premier League table.