Losing weight after 40

01The short answer

02Metabolism: what the 2021 study says

A study published in Science in 2021, led by Herman Pontzer's team, concludes that in adults, daily expenditure stays stable from 20 to 60, even during pregnancy, before declining later. If your weight goes up after 40, it is better to look at your week — time sitting, sleep, meals — than to blame your metabolism, and to talk to your doctor if something has changed.

03Muscle, on the other hand, declines

A review published in 2012 in Frontiers in Physiology estimates muscle mass loss, in cross-sectional studies, at about 0.47% a year in men and 0.37% a year in women, and notes that strength declines 2 to 5 times faster than mass. The Menopause Society, for its part, states that women lose 3 to 8% of their muscle mass per decade after age 30.

Strength training helps, without working wonders. According to a meta-analysis published in 2025, it probably improves strength and physical function in older adults who have lost muscle. In a 6-month trial cited by Obesity Canada, in 136 older adults with abdominal obesity, muscle mass increased by about 1 kg with strength training, alone or combined with aerobic training.

04What to aim for each week

The Canadian 24-Hour Movement Guidelines give adults aged 18 to 64 simple benchmarks: at least 150 minutes of moderate-to-vigorous activity a week, muscle strengthening of major muscle groups at least twice a week, 8 hours or less of sedentary time a day, and 7 to 9 hours of good-quality sleep. After 65, they add activities that challenge balance.

For weight loss, the American College of Sports Medicine associates more than 250 minutes of activity a week with clinically significant weight loss. Obesity Canada also notes that physical activity, with and without weight loss, can improve many cardiometabolic risk factors: the benefit does not show on the scale alone.

05The real challenge: your week

At 40, the obstacle is often the calendar: work, children, commuting. A fixed appointment solves part of the problem, because it no longer has to be negotiated every evening. The Canadian obesity guidelines also focus on habits: precise goals, tracking what you do, obstacles worked through one at a time. For one-on-one support, Joanie, a certified NOOM coach, offers private 60-minute sessions on request, tailored to each person's needs and goals.

06Joanie's classes, at 40 and beyond

Joanie Roussy's women's classes, at noon on weekdays, mix cardio and strength: Strong Nation™, Bootcamp and Zumba®, with no experience needed, and the first week is free. Adult karate, which is mixed, is also open to everyone from 14: Starting Kyokushin after 40 says what changes and what does not, and the first class is free.

07On the island: leaving a Pointe-Nord office

Do you work on Nuns' Island, at the Bell campus or in another Pointe-Nord office? An after-work activity near Pointe-Nord answers the questions that come up when you leave the office. The dojo is at 550 chemin du Golf, suite 010, in the borough of Verdun: whether you come from Verdun or from the island, getting to the dojo maps the way, and the schedule gives the days: women's classes at noon, adult karate in the evening.

Sources

1. Pontzer et al., Science (2021) — doi.org/10.1126/science.abe5017
2. Mitchell et al., Frontiers in Physiology (2012) — frontiersin.org/articles/10.3389/fphys.2012.00260/full
3. The Menopause Society, “MenoNote: Midlife Weight Gain” (2025) — menopause.org/wp-content/uploads/for-women/MenoNote-Weight-Gain.pdf
4. Yan et al., meta-analysis, Aging Clinical and Experimental Research (2025) — link.springer.com/10.1007/s40520-025-03235-w
5. Obesity Canada, chapter “Physical Activity in Obesity Management” (2020) — obesitycanada.ca/wp-content/uploads/2020/08/Physical-Activity-in-Obesity-Management.pdf
6. CSEP, Canadian 24-Hour Movement Guidelines, adults 18–64 (2020) — csepguidelines.ca/guidelines/adults-18-64/
7. CSEP, Canadian 24-Hour Movement Guidelines, adults 65 and older (2020) — csepguidelines.ca/guidelines/adults-65/
8. Donnelly et al., American College of Sports Medicine position stand, Med Sci Sports Exerc (2009) — doi.org/10.1249/MSS.0b013e3181949333
9. Obesity Canada, chapter “Effective Psychological and Behavioural Interventions in Obesity Management” (2020) — obesitycanada.ca/?p=4608

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