If you’re finding yourself gaining weight when exercising, it can be incredibly disheartening. You show up at the gym, push through spinning classes, HIIT sessions, or long jogs, and yet the scale doesn’t budge.
You might even notice clothes fitting tighter around your waist instead of looser.
For many women in their 40s, 50s, and 60s, this is a familiar frustration, especially when they’ve been trying to reclaim their bodies after menopause.
It’s exhausting to give so much effort and feel like your body isn’t responding. You might feel stiff joints after workouts, sore knees or hips, or a general ache in your back.
It can make you dread summer clothes or holidays, or push you to hide behind baggy tops and elasticated waistbands. And emotionally, it can chip away at your confidence, making you feel older or less capable than you really are.
But you have to remember, it’s not your fault, and it’s absolutely possible to reverse this trend with the right approach.
In this article, we’ll explore why women over 40 can experience gaining weight when exercising, why traditional cardio might be holding you back, and how to shift your workouts and lifestyle so that they actually work for your body.
Why Exercise Can Make You Gain Weight After 40
It sounds counterintuitive considering exercise is supposed to burn fat, not make you gain it. But for women in their 40s and 50s, certain workouts can trigger hormonal and metabolic changes that cause the exact opposite effect.
1. Cortisol and the Stress Response
One of the biggest misconceptions is that more exercise automatically equals weight loss. Many women spend hours doing high-intensity cardio or long runs, thinking it will burn off stubborn belly fat, only to find the opposite happening.
The reason often comes down to a combination of hormonal changes, stress, and exercise type. As women age, oestrogen levels decline, which impacts how the body responds to stress.
High-intensity cardio and long-duration workouts spike cortisol, the stress hormone. In younger bodies, short bursts of cortisol are fine, but for women over 40, elevated cortisol over time can block fat loss, especially around the midsection.
High cortisol also disrupts leptin and insulin which are the hormones that regulate appetite and blood sugar. This can lead to cravings for comfort foods, energy crashes, and a metabolism that seems to stubbornly resist all your efforts.
Add the demands of work, family, and life stress, and it’s easy to see why exercising hard without the right strategy can actually lead to weight gain rather than fat loss.
2. Too Much Cardio Can Slow Metabolism
Cardio has long been seen as the go-to for fat loss, but when done excessively, it can actually lower your metabolism. Endurance workouts teach your body to become more efficient — which means it burns fewer calories over time.
For women over 40, who already experience a natural decline in muscle mass, this can make it even harder to maintain a healthy metabolism. If you’re spending hours on the treadmill or bike but seeing no change in your body shape, this could be why.
3. Overtraining and Fatigue
Overtraining is common in women trying to “fix” a lack of results by exercising even more. But this only digs the hole deeper and your energy drops, sleep worsens, and your body struggles to recover.
The result can show up as chronic inflammation, increased water retention, and hormonal chaos. You might notice the scale creeping up despite your best efforts.
Your body needs recovery time especially as you age to balance hormones and rebuild lean muscle.
“Before I started Trinity I was pretty fed up with the way I felt in relation to my body – my weight had gradually crept up to nearly 80kg. I felt I was relatively fit- an active member of 2 gyms doing regular classes like body attack, body pump, HITT step, balance, yoga/ Pilates going at 6.45am and often after work too. I walked quite a bit and did at least 5k steps a day. I was frustrated, and resigned to the fact that I was developing middle-age spread and nothing would work. In just over a year with Trinity, weight wise I have lost 13kg. This is about more than weight or size though- I feel so much better in myself-energy wise, confidence wise and mentally.”
– Helen Huntington (57), Trinity Client
Workouts To Be Wary Of Over 40
Not all workouts are created equal. Some are simply too intense for your hormonal environment after 40, leading to more stress than fat loss.
1. HIIT Workouts
HIIT (High-Intensity Interval Training) became a fitness trend because it burns a lot of calories in a short time. But for women in menopause, it’s often too much stress on the body.
The repeated bursts of all-out effort push cortisol levels sky-high, especially when done multiple times per week. This can trigger fat storage, increased appetite, and even muscle loss over time.
HIIT can also aggravate joint pain, which is a common issue during menopause as oestrogen (which naturally lubricates joints) declines.
2. Long-Distance Running or Endless Cardio
Endless cardio sessions, like long-distance running or hours on the cross-trainer, raise cortisol and break down muscle tissue. The longer the workout, the more stress your body experiences, particularly when paired with under-eating.
This means you might burn calories in the moment, but over time, your body adapts by slowing metabolism and holding onto fat. You’ll likely feel tired, hungry, and frustrated.
3. Bootcamps and Circuit Classes
Bootcamp or circuit-style workouts combine cardio and strength, but they often push you beyond your limits without proper recovery.
These sessions typically involve jumping, sprinting, and minimal rest, which raises cortisol and can cause inflammation and injury, particularly if you’re already carrying extra weight.
Instead of feeling energised, many women leave these classes drained, sore, and craving carbs. It’s a sure sign your body is overstressed.
“When I started Trinity I was healthy and active but didn’t feel that my body reflected that at 77.6 kgs. I’d started playing netball again but it didn’t seem to be making any difference and I was the largest I’ve ever been. I was worried this was just how it was going to be as I got older despite having kept very active throughout my life and having had a decent diet. I am not sure there are words to describe the transformation I have been through over the last 18 months with Trinity. The physical transformation has felt fantastic I am 13.1 kgs lighter but the consequent mental transformation has been even better. My self-confidence has soared.”
– Rachel Crookes (46), Trinity Client
What Exercises to Do Instead to Support Your Body
The key to transforming your body in your 40s and beyond isn’t working harder, it’s working smarter. The right workouts will balance your hormones, lower stress, and help your body become more metabolically efficient.
1. Strength Training (The Secret to Long-Term Fat Loss)
Strength training is the most effective exercise for women in menopause. Lifting weights (or using resistance bands or bodyweight exercises) builds lean muscle, which naturally raises your metabolism.
Even when you’re not exercising, that extra muscle helps you burn more calories at rest, which makes it easier to lose fat without living in the gym.
It also improves insulin sensitivity, supports bone density, and balances hormones which are all crucial during menopause.
Start with full-body strength workouts two to three times a week. Focus on controlled movements like squats, glute bridges, push-ups, and rows, using weights that challenge you but still allow good form.
Here is a 10 minute strength training workout to get you started:
2. Low-Impact Training
Low-impact workouts, such as Pilates, swimming, or walking, allow your body to stay active without spiking cortisol. They help manage stress, improve flexibility, and support recovery between strength sessions.
The women we coach in our Fit Over 40 Programme often notice faster results when they swap high-impact exercise for this low-impact approach. They burn more fat, experience fewer cravings, and see visible toning within weeks.
3. Increase Daily Movement (NEAT)
You don’t have to spend hours in the gym to see progress. Non-exercise activity, known as NEAT, makes a huge difference. This includes walking, taking the stairs, cleaning, gardening, or playing with your kids.
These activities keep your body moving, your blood sugar stable, and your metabolism active, without the stress response caused by intense workouts.
Aim for 8,000–10,000 steps per day and you’ll be surprised how much it supports your fat loss without any added strain.
The Bottom Line
Exercise should make you feel stronger, not heavier or more exhausted. If you’ve been working harder than ever with little to show for it, it’s time to change your approach.
After 40, what your body really needs is smarter, hormone-friendly movement that lowers stress and builds strength.
By focusing on strength training, daily activity, and recovery, you can finally see your efforts pay off, and start feeling like yourself again.
Watch How Rebecca Dropped 3 Stone in Her 50s
How Trinity Can Help You Get Results That Last
At Trinity Transformation, we specialise in helping women over 40 lose fat, tone up, and feel confident again, without exhaustion or restriction.
Our Fit Over 40 Programme is designed around how your body truly works at this stage of life. We use low-impact strength workouts, personalised nutrition guidance, and expert support to help you:
- Drop 1–2 dress sizes in 12 weeks
- Balance hormones and beat stubborn belly fat
- Rebuild muscle, strength, and confidence
- Regain energy and feel in control of your body again
With over 7,000 women transformed and a 97% success rate, you can finally see real, lasting results, without burning yourself out.
