What is the pre-season lactate test and why do Liverpool FC do it?

Liverpool’s pre-season gets underway on Friday and it typically sees players take the lactate test. But what is the lactate test and how does it work?

This week sees Arne Slot welcome the first wave of players back for his first pre-season training sessions as Liverpool’s head coach.

At least 14 of the first team won’t be in attendance due to internationals, but for those that are there, they will be subjected to a gruelling lactate test.

The first days of pre-season are allocated for testing the squad’s fitness levels before ball work is slowly integrated when players are back up to the standard required.

It has become a tradition at Liverpool for the first team to be put through the lactate test on day one, with the endurance exercise dreaded by many within the squad.

In 2022, the Reds mixed it up with the introduction of fractional exhaled nitric oxide (FeNO) testing, but they returned to their traditional ways this time around.

So what is the lactate test and why do the Reds do it?

As explained by EKF Diagnostics, who provide some of the equipment needed to implement the lactate test, it is used to “learn the highest intensity at which a footballer can train or compete before hitting the wall from high levels of blood lactate.”

Players are tasked with running around one of the Kirkby pitches at a series of different intervals and paces, with blood tests taken after every interval to test for levels of lactic acid.

If a player is above a certain amount, they will then drop out of the drill – James Milner was typically the last man standing each time until he left, but Mo Salah took his crown last year.

“Once you surpass this threshold, lactic acid will start to build up in your muscles faster than your body can remove it, eventually leading to fatigue,” EKF Diagnostics continues.

“Testing and improving lactate threshold within a training program can be used to make stronger and faster athletes.”

In short, if the pace and intensity a player can manage with their lactate threshold is higher than their opponent, they will be able to last longer at the level required.

Like with Klopp, this will be essential for Slot’s system which is not wholly centred around outrunning the opposition but still demands the highest level of fitness possible.

Andy Robertson discovered this the hard way when he took his first lactate test as a Liverpool player, with the left-back detailing his experience in an interview with Open Goal in 2018.

“It’s horrible, running round the pitch, I’m doing it with Danny Ings and that,” Robertson recalled.

“My medical went on for two days – it was quite a long medical – so I wasn’t eating, I wasn’t doing this and that. I was fit because I had three weeks at Hull and I was looking after myself.

“So I’m taking the lactate test and I’m thinking, ‘my stomach’s a bit dodgy here’. I started gagging and I was sick everywhere.

“Halfway around I had to stop and be sick, then I tried to catch them up because I’m thinking, ‘I can’t drop out at this point’, because this point was like you are super unfit, that was the point you had to get by.

“So I was sick around the pitch, then I had to stop because they have to take the blood out your ear, and I was sick when I was getting my blood taken.

“I went another lap and I was like ‘I need to stop’.”

Fortunately, Robertson was eventually able to prove himself to Klopp and has not looked back since.

While the lactate test is not unique to Liverpool, it is another example of the marginal gains enjoyed by the club and remains the case in 2024.