Teenagers embrace 'cut and bulk' regimes as social media fuels push for sculpted physiques

A growing number of teenagers are adopting "cut and bulk" cycling and intensive gym routines to achieve highly defined muscles, driven in large part by social media content that glamorises sculpted physiques. Health professionals warn the trend can conflict with adolescent growth needs and, in some cases, contribute to disordered eating and other health risks.

The cut-and-bulk approach typically involves a bulking phase in which daily calorie intake is raised well above recommendations to gain muscle and size, followed by a cutting phase to reduce body fat and reveal muscle definition. Hashtags such as #shreddedphysique have been viewed billions of times, and videos show boys as young as 13 and 14 flexing in school uniform or sharing training and nutrition tips online.

The trend is visible across several profiles interviewed by BBC reporters. Fourteen-year-old George Holland, who began going to the gym at 11, competed in the under-19s category of the National Amateur Body-Builders' Association finals and won bronze. After moving to a commercial gym and seeking mentorship from older lifters, George said he is now coached by a former Mr Universe and is bench-pressing 140kg, squatting 180kg and deadlifting 200kg. He told reporters he eats six meals a day and is currently "bulking" on about 4,100 calories a day before planning a cut down to roughly 2,200 calories over a 16-week cycle. He posts training updates to thousands of followers on TikTok and Instagram and described gym training as beneficial for mental health, fitness and discipline.

George Hazard, now 17, started working out at 12 during the Covid-19 lockdown with a pull-up bar and a few weights in his garage. He trains five to six nights a week and said the gym has been important to his mobility following a leg-lengthening operation. He described using social media to learn training methods and said he evaluates content by checking for links to studies or evidence-backed sources, though he acknowledged the difficulty of following strict diets when living at home.

Eighteen-year-old Nat Walney described experimenting with "dirty bulking" between ages 13 and 16, consuming large amounts of highly processed food to gain size. Nat said the approach produced visible changes but left him with digestive issues and acne. He later shifted to a self-directed regimen that includes prolonged intermittent fasting and what he described as a raw carnivore-style diet of raw meat, eggs and raw milk. Nat said he has used online tools, including AI chatbots, to help plan fasting and dietary strategies, and expressed an intent to promote his approach online while acknowledging he would change course if it harmed his health.

Children's dietitians and coaches interviewed alongside the teenagers said there is nothing intrinsically wrong with interest in fitness, but cautioned that extreme or restrictive eating and very high training loads can be inappropriate during adolescence. Lucy Upton, a children's dietician, said social media content sometimes mixes a kernel of scientific fact with context that does not apply to young people. She advised scrutinising the credentials of those offering nutrition advice, being wary of sellers, and seeking guidance that accounts for an individual's growth needs.

Sam Grady-Graham, a GB Boxing coach, warned against restrictive eating regimes in the teenage years, noting that growth between ages 12 and 18 is rapid and requires a nutritionally complete diet. He recommended a balanced diet including fruit, vegetables, grains, proteins and dairy, and emphasised proper technique and progressive training rather than pushing intensity too quickly. "Movement over muscle" was his guidance for setting a long-term foundation.

Experts also highlighted clinical risks associated with some practices observed among young people trying to get very lean. Muscle dysmorphia, a form of body image disorder characterised by a belief that one's body is insufficiently muscular, can lead to excessive training and disordered eating. Prolonged fasting or very low calorie intake during adolescence can impair hormone balance, growth and organ function, clinicians say, and fasting for multiple days carries additional medical risks. Some sports nutritionists caution that cycles of bulking and aggressive cutting can be physiologically stressful if not planned and supervised by qualified practitioners.

Although some teenagers in the interviews described perceived benefits — increased confidence, discipline and improved mobility after surgery — experts emphasised that those outcomes do not require extreme diets or training. They urged parents, coaches and young athletes to seek evidence-based guidance from credentialed health professionals when planning training and nutrition, and to be cautious about following unverified online recommendations or AI-generated plans without clinical input.

As the aesthetic ideal of a tight, sculpted torso spreads through social media, clinicians say the priority for teenagers should remain balanced nutrition, supervised training, and attention to mental as well as physical health. Those with concerns about extreme dieting, obsessive exercise or body image should be offered assessment and support from appropriate health services.