Teenagers adopt 'cut and bulk' cycles and restrictive diets as social media fuels desire to get ripped

A growing number of teenagers are adopting the "cut and bulk" approach used by bodybuilders — deliberately alternating periods of overeating to build muscle with calorie restriction to reduce fat — driven in large part by social media trends that celebrate highly defined physiques.

Videos tagged with hashtags such as #shreddedphysique have been viewed billions of times, and gym jargon once heard mainly in locker rooms is now common among school-age boys. For some adolescents the regimen involves occasional resistance work and higher-protein meals; for others it has become an all-consuming cycle of calorie counting, daily training and closely following online coaching and routines.

Fourteen-year-old George Holland is among the most visible of the teenagers who have embraced competitive-style bodybuilding. He joined a gym at 11 and, after moving to a different facility with fewer youth restrictions, began lifting much heavier weights under coaching from a former Mr. Universe. George says he now bench-press 140kg, squats 180kg and deadlifts 200kg. He trains on a cycle of four days on, one day off, then another four days on, and says he eats six meals a day while juggling school. Currently in a "bulking" phase, he reports consuming about 4,100 calories a day before planning a 16-week "cut" that will reduce daily intake to around 2,200 calories. He also posts training content to a combined social-media following of about 140,000.

Not all teenagers take that route. George Hazard, 17, began working out at home during the COVID-19 lockdown and built his routine with minimal kit. He trains five to six nights a week and says lifting has helped him stay mobile following a leg-lengthening operation. Hazard says he finds both useful fitness information and misleading advice on platforms such as TikTok, and that he tries to identify creators who link to scientific studies. He acknowledges the practical limits of strict meal plans in a shared family household but says a higher-protein diet has helped his training.

Eighteen-year-old Nat Walney described a progression from "dirty bulking" — large amounts of calorie-dense, ultra-processed foods — to more extreme dietary choices. Nat says he experienced acne and digestive problems after earlier bulking, then adopted a largely raw carnivore-style diet of steak, eggs and raw milk and an intermittent fasting routine that can last 20 hours a day. He said he used an artificial intelligence tool to research fasting and other approaches and that he would adjust his routine if it proved harmful. Medical experts caution, however, that prolonged fasting and highly restrictive diets can be risky for adolescents who are still growing.

Health professionals interviewed by reporters say there is nothing inherently wrong with teenagers wanting to be fit, but they stress that the pursuit of a particular look can prompt harmful behaviours. Children's dietician Lucy Upton warned that social-media content often presents a simplified or decontextualised version of evidence; what appears to cite a study can be unrelated to the advice being promoted. She urged viewers to consider whether content creators have clinical expertise and to be sceptical when people are selling supplements or programmes.

Sam Grady-Graham, a GB Boxing coach, said restrictive eating regimes among people aged 12 to 18 can be particularly problematic because growth during those years is rapid and nutrition needs are high. He recommended a balanced diet from main food groups and emphasised proper movement and lifting technique over rapid increases in heavy-weight training. Sports nutritionists also warn that extreme calorie cycling and dietary restriction can affect hormone levels and growth and may contribute to disordered eating patterns, including muscle dysmorphia, an obsessive belief that one's body is insufficiently muscular.

Experts also expressed concern about how young people find and use information online. While some creators link to peer-reviewed research, others mix factual points with unproven claims, and AI tools can produce advice of variable quality. Upton advised checking a presenter's qualifications and whether recommendations are personalised and evidence-based.

Parents, coaches and leisure centres say they are seeing more teenagers take an interest in strength training, which can have physical and mental-health benefits when supervised and balanced with appropriate nutrition. At the same time, clinicians and trainers call for clearer guidance for under-18s on safe training loads, adequate caloric intake for growth, and how to evaluate online fitness advice. Platforms that host content and commentators who promote extreme diets for young audiences have been urged to make the provenance and safety of their guidance clearer.

As the trend continues, professionals stress moderation and monitoring. Proper technique, a nutritionally balanced diet, and age-appropriate programming are central to reducing risk. For adolescents, advisers say, the emphasis should remain on long-term health and development rather than short-term changes in appearance.