I'm a World-Renowned Expert: Why Strength Training Matters for Women in Their 30s, 40s, 50s and Beyond

You'd have had to have been living under a rock not to have heard of Krissy Cela, one of the most globally renowned personal trainers and fitness entrepreneurs.

The Albanian-born, LA-based entrepreneur first launched her career while studying law in London, sharing gym content online that quickly amassed an engaged and loyal following thanks to her gimmick-free, reliable approach.

Following her online success, Cela launched her first business, EvolveYou, a global fitness platform with one simple aim: to encourage more women to take up strength training and build their confidence in the weights section.

In 2020, she went one step further, launching her now multi-million-pound activewear brand, Oner Active and appointing Zach Duane, the former CEO of Victoria Beckham, to help steer the business. The performance-led brand's ethos is simple: to create workout kit that performs as well during serious training sessions as it does throughout everyday life - think functional, minimal pieces designed with both lifting and looking good in mind.

And since then, both brands have gone from strength to strength: 2025 figures show Oner reported £80.8 million in annual sales, plus a £8.4 million profit for 2024, doubling revenue compared to the previous year.

Cela's aim is simple: to make strength training more accessible, particularly for women navigating confidence, consistency, and long-term health goals. Her school programme, Project Power, sees Cela and team head into schools and demystify weights to young girls; she's adamant to reframe exercise as something empowering rather than punishing.

What makes Cela unique is her unwavering passion for strength training and desire to spread the magic far and wide. Strength training has changed her life, and she's built an entire business empire around sharing that with you. EvolveYou shares plans to make lifting less intimidating; Oner sells clothes that make you feel empowered while doing so; and Project Power gives the next generation the tools to move their bodies without fear.

Below, Cela shares her first Marie Claire Masters piece, centred on why, exactly, strength training is so pivotal in your 30's, 40's, 50's and beyond. She knows first-hand that it should be a non-negotiable in your workout routine, and breaks down how the workout is about far more than just aesthetics; rather, the key to mental strength, hormonal health, and metabolic resilience. Because building muscle is one of the most powerful long-term investments you can make in your body.

Why you should make strength training a part of your weekly workout rotation, according to Krissy Cela

I first discovered strength training while studying law at university, and I immediately fell in love with the empowering feeling that it gave me. I loved it so much that I went on to obtain a Personal Training qualification so I could help more women feel the way that I feel.

Strength training has always represented a determined, goal-oriented mindset and unwavering work ethic; it can also play such a pivotal role in building confidence, plus help to balance/reset your nervous system and clear your mind, all while helping your body be the best it can be. The power of strength training never ceases to amaze me.

Strength training has always made me feel stronger, not just physically but mentally as well. After having my son, being in the gym helped me to regain a sense of routine and to reconnect with myself. Seeing what my body is capable of achieving has always given me confidence, whether that’s in the gym or anywhere else.

Training to enhance both body and mind

I’ve always believed that every woman should strength train to enhance their physical and mental well-being - it’s about building strong bodies and even stronger minds. This is why I started both EvolveYou and Oner Active: to enable and empower as many women as I can to move their bodies.

Strength training especially important for women. When we're young, strength training helps us build a strong foundation by increasing muscle mass, improving bone density, boosting confidence and creating healthy habits that support us for years to come. As we age, strength training becomes even more important because we naturally begin to lose muscle and bone density, particularly during and after menopause. By continuing to strength train, we can maintain our independence, support our metabolism, reduce the risk of injury and osteoporosis, and stay strong enough to do the things we love.

It’s imperative that we encourage young girls to create healthy habits as early on as possible, which is why we introduced our schools initiative, Project Power, in 2023. We know there are so many factors leading to young girls disengaging with physical activity, including body image and puberty, so our mission really is to transform the way that young girls perceive it and empower them to want to move their bodies.

Project Power aims to introduce strength training to young girls by visiting schools nationwide and hosting women-led, women-only workshops with young girls to educate them about movement, strength training and confidence. We also recognise that the cost of activewear can be a barrier to entry for a lot of girls and their families, so at each of these workshops, we provide the girls with kits of free suitable activewear (a sports bra, T-shirt and leggings), which will support them as they grow. To date, we’ve hosted over 4,500 workshop participants and gifted our activewear kits to over 18,000 teenage girls.

Feeling empowered > fear of getting “bulky”

The biggest myth about strength training is the trope that women who lift weights are bulky and ‘masculine’. Nonsense. A woman who lifts is strong, and while strength looks different for every body, strength is undeniably and universally beautiful.

Thankfully, I think people are starting to move away from this narrative. While historically, women were told that strength training and lifting heavy was reserved for bodybuilders and that low-intensity movement and cardio were more effective ways of maintaining a ‘feminine’ figure, social media has given us clear, tangible examples of the real impact and results that strength training can have on the body.

One of the most powerful things about strength training is that it shifts your focus from how your body looks to what it can do. As you progress in your training, you start to appreciate your body for its strength, resilience, and capability rather than just its appearance.

Moving your body should never be about shrinking yourself. It’s about feeling stronger in who you are and what you’re capable of, whatever that may look like.

If you feel nervous walking into the weights section, know that your first time in the weights section can be terrifying. That said, doing anything for the first time can feel intimidating, and as corny as it might sound, the key really is remembering that you’ve done the hardest part - showing up for yourself. Gym-timidation and nervousness are so real, especially for women.

Moving your body in a way that works for you

I’m a believer in moving your body in a way that fits your lifestyle and is something you can stay consistent with. That said, for women looking to build strength and see noticeable benefits, I’d recommend aiming for around three strength training sessions per week.

Combined with a balanced, nutritious diet, three sessions can be enough to improve strength, increase muscle mass, boost energy levels, and support overall health. Consistency is far more important than doing the perfect workout plan, so finding a routine that you genuinely enjoy and can maintain long-term is key. I personally have really been enjoying mixing low-intensity movement with my strength training program, and I feel the most confident I've ever felt.

Mastering a handful of fundamental strength-training exercises can provide a strong foundation for lifelong fitness and overall well-being. Squats, deadlifts, lunges, rows, push-ups, and core stability movements help develop strength, balance and stability while supporting healthy bones and making everyday activities easier.

Getting started - wherever you currently are

There is no fitness level you need to reach before you begin. Strength training is for everyone, and every single person in the gym started somewhere. Don’t put pressure on yourself to walk into the gym and lift the weight you’re seeing other people lifting on Instagram or TikTok; it’s your own journey, and progress looks different for everyone.

Focus on building confidence, proper form and technique and remembering to celebrate the small wins along the way. Starting at the lower end of the weight rack and working your way up will be one of the most rewarding feelings. Continue showing up consistently and trusting the process.

Girl, pick up those weights and start lifting!

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