When Arsène Wenger took over at Arsenal in 1996, English football's relationship with fitness and nutrition was still, by his standards, close to amateur. Post-match pints and pre-match fry-ups were an accepted part of a footballer's routine at plenty of clubs, and the idea of individually tailored training loads or dietary plans was treated as a continental eccentricity rather than a serious professional standard.
Wenger changed it almost immediately, and largely by insisting rather than persuading. He introduced structured stretching routines, cut sugar, alcohol, and fried food from the club's approach to player diets, and brought in specialist staff to manage fitness and injury prevention in a way English clubs simply hadn't organised before. Some senior Arsenal players were reportedly sceptical at first - it was, after all, a significant change to habits built up over entire careers - but the results were hard to argue with once they arrived.
The effect showed up on the pitch within a couple of seasons: an Arsenal squad that could sustain a higher tempo for longer, recover faster between matches, and avoid the kind of muscular injuries that had quietly shortened plenty of careers under the old approach. It's a meaningful part of why Wenger's Arsenal teams, built around players well into their thirties like Tony Adams, could keep performing at the top level for so much longer than the conventional wisdom of the time expected.
What happened next is arguably the bigger legacy. Within a few years, other Premier League clubs had quietly adopted versions of the same approach - specialist nutritionists, structured recovery, sports science departments that would have been unthinkable at an English club a decade earlier. Wenger didn't just build a great Arsenal team. He forced an entire league to take professionalism more seriously than it had been willing to before he arrived, and most of what's now considered standard practice in the Premier League can be traced back to methods he was ridiculed for suggesting in 1996.