For those not involved in the World Cup, and selected others, Jurgen Klopp's side began on July 2nd, with the next month or so seen as pivotal. The work done at this stage can help them prepare for what those at Anfield hope is a successful season.
While the arduous amounts of running is hardly anyone's idea of fun, especially in the searing heat, one player has already managed to stand out in the early fitness testing, although it should hardly be a surprise.
As reported by the Daily Mail, despite being one of the older member's of Klopp's squad at 32, James Milner's fitness levels remain as high as ever, by outperforming his teammates during a lactate fitness test, which is used to measure aerobic endurance.
Taking a blood sample after every lap, if the levels of lactic acid exceeded a certain threshold, they were forced to drop out, with Milner the last one left standing, running 800m laps at 24km/h.
A consummate professional, Milner has become a fan favourite during his time on Mersyside due to his workman-like attitude and effort, while his quality does sometimes go unnoticed.
Last season the former Manchester City man thrived at the heart of Liverpool's midfield, providing 11 assists in 43 league and Champions League games, eight of which came in Europe as the Reds made it to the final in Kiev, and will no doubt play a key role in the season ahead.