At least five Liverpool players currently have hamstring injuries and some reckon Jurgen Klopp's new style of play could be to blame.

One of the German manager's tactics is "gegenpress" which means to press the other team as soon as you lose the ball.

The approach is one of the main reasons Klopp's previous side, Borussia Dortmund, was so successful.

It requires plenty of training which may leave players more open to injury.

Former Liverpool legend Graeme Souness certainly thinks so.

So does the BBC pundit Kevin Kilbane, who watched as Liverpool beat Stoke and picked up more injuries.

"Perhaps it's down to the change in training methods. Under Jurgen Klopp they'll train much harder day in, day out," he said.

"The amount of medical attention footballers get at football clubs now - and also the physical work which is put in - this shouldn't be happening.

"I put down the various hamstring injuries down to Klopp's change in style."

What is the hamstring?

We spoke to sports physiotherapist Colin Paterson. He's the chair of the Association of Chartered Physiotherapists in Sports.

"The hamstring is actually a group of muscles," he explained.

"It is three muscles on the back of your leg that attach to where your bum is and the other end is attached just below the knee."

"It's the group involved in bending your knee and extending your hip, so things like walking and running are typical activities when those muscles will be working," he explains.

So what is 'doing your hamstring'?

Listen to football commentators and you often hear them say "they've done their hamstring".

It means the sudden onset of pain in the back of the leg caused by tearing some of the muscle.

"That can mean that you've torn the muscle quite mildly - a strain or 'cramp like' thing - through to a more severe extreme muscle tear," Paterson explains.

Physiotherapists grade the injuries from one to three. One and two are mild and are usually fixed in a few weeks but "a three" can take much longer as there is "more healing" to be done.

Is Jurgen Klopp pushing his side too hard?

Some ex-players think so and even the man himself has admitted there are tough demands made on Premier League players.

We only recover. There is no training Jurgen Klopp

"Maybe I could look at our training methods but we don't train - we only recover. There is no training," he said.

"I'm responsible for these things and if you want to make me responsible for our hamstring strains, then OK."

"Muscles need their rest time and obviously athletes are pushing their bodies to the limit," Paterson adds.

"If an athlete is suddenly doing new movements or doing more of a certain type of sprint, or changing how they would normally play, then it does take time for the body to adapt to be able to cope with that.

"If someone is having to do things differently then they are at risk of getting injuries until their body gets used to it."

Do Liverpool need to get fitter?

Well, not exactly. Liverpool's players will already by incredibly good athletes but they may not be used to Klopp's new tactics.

"Changes in patterns of movement do change the way the body has to work," Paterson argues.

"The body has to take time to change co-ordination and to get a bit fitter.

"So it's a case of adapting to what they are now having to do."

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