Writer, educator and parent coach Oona Hanson grew up when women were encouraged to pursue the “Buns of Steel” look but discouraged from strength training because they might become bulky. Exercise was framed around appearance and becoming smaller, not around how much weight a woman could lift.

That message is shifting as more women learn about the health benefits of building muscle, particularly during middle age. Strength training can help protect bone density and support overall wellbeing as people grow older.

Yet the changing fitness culture may carry another risk. Pressure to lift heavy weights, track protein and build visible muscle can become an unhealthy preoccupation with food and exercise, replacing one demanding appearance standard with another.

Liz Bucar, a professor of religion at Northeastern University in Boston, once approached fitness through a cardio focused lens and was “always trying to be smaller.” Now in midlife, she strength trains with a coach.

Bucar, author of “Beyond Wellness: How Restoring the Religious Roots of Spiritual Practices Can Heal Us,” sees the transition from counting calories to making progress in the weight room as powerful. She described the shift as “more protective of our health” and said it “pushes back against conventional beauty norms.”

That change can also help women reclaim exercise from diet culture. Jamison said fitness had been toxic for many women because of the way it became entwined with attitudes about food, bodies and the expectation that women should take up less space.

Jamison credits strength training as a critical part of her recovery from an eating disorder, but she remains wary of the trend’s framing. “‘Strong is the new skinny’ should be like a Bat-Signal to somebody like me, right? Like, oh, that sounds so great. But I think it’s also very complicated,” she said.

Women of many sizes are trying to build strength, yet social media frequently presents a narrower image. Jamison said the dominant message often appears to be about being strong and skinny, creating another potentially damaging body standard.

Keri Harvey, a certified personal trainer and joint owner of Form Fitness Brooklyn in New York, said larger women who lift weights remain underrepresented. Strong bodies can also have fat and cellulite, she said, even when they do not resemble bodies shown on Instagram or magazine covers.

Building strength can be physically at odds with making the body smaller. Harvey tells clients that muscles need room, meaning stronger back muscles may require a larger bra size and stronger biceps may make a shirt fit more snugly.

Women should expect their bodies to change as they gain strength, Harvey said, but those changes may not match their assumptions. Accepting that possibility can be difficult when women have repeatedly been taught that their bodies should remain small.

Jamison warned that strength training can still promote a highly aspirational appearance. The language may focus on strength, but the visual ideal can remain a very lean body with clearly visible muscle.

Megan Hellner, a registered dietitian and cofounder of AthleatMD, treats athletes with relative energy deficiency in sport, or RED-S, and eating disorders. She said the culture can feel like women are exchanging one narrow ideal for another, particularly when they pursue what she calls the “athletic aesthetic.”

At the same time, building muscle requires energy. Unlike an emphasis on thinness that encouraged calorie restriction, strength and muscle development require people to eat enough to support their bodies.

“Strength and building muscle require that we eat. We have to feed the muscles, and so a lot of the categories of foods that have been demonized in other trends are things that we need in order to build the muscle,” Harvey said.

Fixation can still emerge through progressive overload, a training approach centered on increasing the amount of weight a person can lift. Harvey said the central goal should be feeling strong enough to live one’s life, rather than constantly believing that no amount of training is sufficient.

Hellner advised women to notice physical warning signs before they become severe. Pain, injury, refusal to rest and intense distress when a training session is missed can all indicate a troubling relationship with exercise.

Rest is also a necessary part of strength training, particularly for people accustomed to intense daily cardio sessions. Harvey said muscles need time to become comfortable with a movement and a load because inadequate rest can tear the body down.

Hellner encouraged women to view food as more than fuel for workouts. The body also needs nourishment for basic life processes, hormone production, organ function, daily activity, relationships, community and joy.

Harvey and Jamison emphasized balance and routines shaped by personal needs. Women seeking to feel less stiff in daily life do not need to train as if they are entering a powerlifting competition, and lasting goals can extend beyond appearance or the latest fitness trend.

Jamison argued that fitness should be understood through a more inclusive range of bodies than social media typically shows. “That should not be the only picture of health, strength or fitness,” she said of the lean and visibly muscular ideal.