When? I mean, just watch Pumping Iron again you can see when he flexes his calves how deep the striations are. I don't think you could do that with a silicone injection
You can see them on the inside of his calf in that movie.. Today they put two implants in each calf.. They slide the implant down from behind the knee in the back of the leg, under the muscle.. You still can see the striations because it's under the muscle..
