The designer shared the snap on his Instagram over the weekend, with the caption: "Lunchtime workout at the legendary City Gym."
It comes after Alex first stunned fans with his muscular physique in 2020 when the 59-year-old shared a picture on his Instagram Stories showing the results of his Covid lockdown workout.
Fans flooded the comments of his latest Instagram post, with one claiming he was bigger than Dwayne 'The Rock' Johnson.
"Beast mode on," one commented.
"Rig city," another said.
"Dude your journey has been impressive. Looking great," a third added.
In 2020, the designer told SBS going to the gym and working out kept him in peak physical and mental condition, allowing him to tackle whatever challenges he was faced with in the fashion industry.
“In the beginning, I didn’t look at exercise and training as a science. Sure, I would train hard back then but I didn’t eat well afterwards,” he said.
After his trainer Billy Kokinos explained his diet was 70 per cent of his results, Alex began eating "clean" during the week and only indulged on the weekend.
His new body shape has meant that the designer has needed his clothes tailored and taken in.
“I buy shirts to fit me in the shoulders and the chest and just get them altered in the middle. It’s a very European thing to alter clothes for both men and women. You buy something off the rack and if it’s not right, you get it tweaked.”
Alex had been previously criticised for his image when he appeared as a judge on Australia's Next Top Model in 2016.
Contestant Kassidy Ure hit out at the designer who critiqued a photo of her, saying: "He just blatantly didn't like my photos, and he's like, 'I don't like it. You look catalogue'."
"Thanks, at least my lips are real," she added, accusing of Alex going under the knife.
In 2013, Alex told Yahoo Lifestyle he had only had botox and fillers.
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