The science is more compelling than most training plans account for. Here's what the research actually says — and what I do about it.
Most women who train hard think about their legs in terms of aesthetics or performance. How they look. How they feel. Whether the squat depth is improving.
What almost nobody talks about is what strong legs are actually doing for your brain.
In 2016, researchers at Kings College London published the results of a 10-year study tracking 324 women. They measured leg power at the start of the study and then assessed cognitive function a decade later. The findings were striking. Women with greater leg power at baseline had significantly better cognitive health ten years on — better memory, faster processing speed, more grey matter volume. The effect held even when comparing identical twins, controlling for genetics, lifestyle, and health factors.
Leg power predicted brain health. Not grip strength. Not lung function. Leg power.
That finding changes how I think about every lower body session I programme — for myself and for the women I work with.
Why legs specifically
The legs contain the largest muscle groups in the body. When you train them seriously — deadlifts, split squats, loaded lunges, kettlebell swings — you're not just building strength in the lower body. You're triggering a cascade of physiological responses that affect the whole system.
Resistance training of large muscle groups stimulates the release of brain-derived neurotrophic factor (BDNF) — sometimes called 'Miracle-Gro for the brain.' BDNF promotes the growth of new neural connections, supports memory consolidation, and has been linked to reduced risk of cognitive decline. The larger the muscle group trained, the greater the stimulus.
There's also the bone density argument, which becomes non-negotiable after 35. Oestrogen decline accelerates bone loss from the mid-thirties onwards. Weight-bearing exercise — particularly lower body resistance training — is the most effective intervention available for maintaining bone density. Walking helps. Running helps more. Heavy loaded squats and deadlifts are in a different category entirely.
And then there's the functional argument — perhaps the most straightforward of all. The ability to get up from the floor, to climb stairs without holding the rail, to catch yourself when you stumble — these are lower body strength qualities. They determine independence in later life more than almost any other physical attribute. You don't lose them suddenly. You lose them gradually, through years of not prioritising the training that maintains them.
What I've noticed in practice
I've been training seriously for over a decade. Lower body training has always been part of my programme, but it's only in the last few years — as I've gone deeper into the research and the professional development — that I've started treating it as genuinely non-negotiable rather than just important.
The shift was partly the Kings College study. Partly the work I've done on mobility and recovery and understanding how the body ages. And partly watching what happens when women consistently prioritise lower body strength over time.
The changes aren't just physical. Women who train their legs seriously — who deadlift, who do split squats, who push through the discomfort of a properly loaded session — carry themselves differently. There's a confidence that comes from knowing your body is capable and getting more capable. That's not a small thing.
What the research says about fast twitch muscle and ageing
Here's the piece most people miss.
There are two types of muscle fibre — slow twitch and fast twitch. Slow twitch fibres support endurance. Fast twitch fibres support power, speed and explosiveness. As we age, fast twitch fibres decline significantly faster than slow twitch ones. This is why older adults lose power before they lose endurance — and why power-focused training becomes increasingly important as you get older, not less.
The lower body movements that develop power — jump training, kettlebell swings, med ball slams, explosive lunges — are the ones that specifically target fast twitch fibres. They're also the ones most women skip, either because they feel too intense or because they're not part of typical gym programming for women.
This is a mistake that compounds over time.
The good news is that fast twitch fibres respond well to training at any age. The research on plyometric training in older women is genuinely encouraging — significant improvements in power, balance, and functional movement after as little as 8-12 weeks of consistent training. The window doesn't close. It just requires deliberate effort to keep it open.
What I actually do
My lower body session runs once a week alongside other lower body work throughout the week. The anchor session looks like this:
Warm up — banded good mornings, glute bridges, dead bugs. Non-negotiable.
Main session — deadlifts at 5 sets of 5, building weight progressively with 2-3 minutes rest between sets. Then a kettlebell swing into broad jump superset, a barbell split squat into jumping lunge superset, a push press into med ball slam superset, and dumbbell bench press to finish.
On weeks when the prowler is available I'll add four to six sets of twenty metre pushes — there is almost nothing more effective for lower body conditioning and mental resilience in the same movement. It is not comfortable. That is the point.
Cool down — 90/90 hip stretch, hip flexor work, hamstring fold, thoracic rotation. Another ten minutes.
The whole session takes around 50-60 minutes. It's the session I protect most in my week. Not because it's the most enjoyable — it isn't always — but because I understand what it's building and what it's protecting.
Get the full workout
I've put together the exact session I run — full warm up, main session with gym and home modifications, and cool down. Free to download.
Important: this session includes explosive, higher impact movements that aren't suitable for everyone. If you're pregnant, postpartum, returning from injury, managing joint issues, or new to strength training, please consult your doctor or a qualified fitness professional before attempting this workout. Listen to your body and modify or skip any movement that doesn't feel right for you.
What to do with this
If lower body training isn't a priority in your current programme, start simple. One dedicated session per week. Deadlifts, lunges, and something explosive. Build from there.
If you already train your legs consistently, go deeper on the power work. Add the jumping lunges. Add the swings. The strength foundation is there — now train the fast twitch fibres that decline fastest and matter most.
The kit built for this session
The Prowess collection was designed for exactly the kind of training this article is about.
Heavy loading. Full range of movement. The session that asks something serious of you.
The leggings you wear for deadlifts and split squats need to perform differently to the ones you wear for a run or a yoga flow. They need to hold under load, move with you through full hip hinge depth, and not shift or compress in ways that limit the movement. Prowess was built around those demands specifically — four-way stretch fabric, high waist construction that stays in place under a barbell, OEKO-TEX® certified to the same standard as everything we make.
And for everything that comes after
The session is the stimulus. Recovery is where adaptation happens.
The Aftermath collection — soft enough to actually rest in, structured enough for the cool down, certified to the same OEKO-TEX® standard as Prowess. Because the 50 minutes after the session matters as much as the 50 minutes during it.
Shop the Aftermath Collection →
Link 'sleep' → the sleep article already live on The Viren Journal
Link 'OEKO-TEX®' → certifications/No Harm Done page
— REFERENCE —
Steves CJ, Mehta MM, Jackson SHD, Spector TD. Kicking Back Cognitive Ageing: Leg Power Predicts Cognitive Ageing after Ten Years in Older Female Twins. Gerontology. 2016;62(2):138-149.