2 20 20-30 20s 25 25-30 30 abdominal abs achievement achieving active activewear activity adult adults and appearance athlete athletes athletic bare being beings body brother brothers build caucasian caucasians challenge challenging chest clothes clothing color colour competition competitive crossfit effort equipment european exercise exercising fit fitness full full-body full-length germany grown-up grown-ups grownup grownups gym gyms human humans image indoor indoors interior interiors length lift lifter lifting machine machines male males man men muscle muscles muscular musculature pack people person persons photo photography photos power practice practicing practise practising shirtless shot shots siblings sister sisters six six-sack sixpack sport sports sportsman sportsmen sportswear stand standing stomach strength strengthy strong success successful to together train training twin twins two view washboard wear weight weightlifter weightlifting weights workout years young