The Germany Under-21 international suffered the injury during a 1-0 defeat by Chelsea in the International Champions Cup in Pasadena in United States on 27 July.
Karius has been ruled out for around two months after the collision with Croatian centre-half Dejan Lovren left the shot stopper with a broken hand.
The 23-year-old was the first of Jurgen Klopp’s seven summer signings after the German star completed a £4.7m move to Anfield from Bundesliga side Mainz.
However, the Liverpool number one is working hard on maintaining his fitness despite his injury setback as he worked out in the gym on Wednesday afternoon.
Karius posted the above video on his Instagram page and wrote the following caption:
“Well, any good comeback needs countless gym hours first.🏋🏼 💪🏼💦 #LFC #DontStop #HardWork #training #LK1 @liverpoolfc”
The Reds goalkeeper will be competing with current first-choice shot stopper Simon Mignolet and Austrian veteran Alex Manninger for a first-team spot this season.
Liverpool were 4-3 winners against Arsenal in their opening Premier League game of the season at the Emirates Stadium.
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