Joanie · Fitness and weight

Build muscle and lose fat: body recomposition

“Body recomposition”, “lean body”, “muscle and strength”: many people want less fat and more muscle at the same time, without necessarily aiming for bodybuilding. This guide says what research shows, why muscle matters even more over the years, and what to aim for each week.

By Joanie Roussy — certified NOOM coach; certified Strong Nation™, Zumba®, Zumbini® and CIRCL Mobility™ instructor; Shinkyokushin black belt karateka, sempai and director of the dojo. Her story.

01The short answer

Yes, you can build muscle and lose fat at the same time: a review published in 2020 in the Strength and Conditioning Journal documents it, even in people who already train, with two keys: progressive strength training and evidence-based nutrition. The Canadian guidelines recommend muscle strengthening at least twice a week. For a regular strength-training slot, Joanie Roussy's women's classes run at noon on weekdays on Nuns' Island; the first week is free.

02The scale does not tell the whole story

A scale measures total weight: it cannot tell muscle from fat. That is the whole point of recomposition. The American College of Sports Medicine summed it up in its 2009 position stand: strength training does not speed up weight loss, but it increases lean mass. Obesity Canada agrees: strength training may help maintain weight or gain a little muscle.

In other words, if you do strength training, also judge your progress by your strength, your stamina and how your clothes fit, not only by the number on the scale.

03What research shows

It is often said that recomposition only happens to beginners or people with excess weight. The 2020 review by Barakat and colleagues brings together, on the contrary, a substantial body of research that also observes it in people with strength-training experience. It identifies two factors: progressive strength training, meaning more demanding over time, and evidence-based nutritional strategies.

For nutrition, Protein and training gives the sports nutrition benchmark for active people; for a plan made for you, the right person is a registered dietitian.

04Why muscle matters for women

Muscle declines over the years. A review published in 2012 in Frontiers in Physiology estimates this loss, in cross-sectional studies, at about 0.37% a year in women, and notes that strength declines 2 to 5 times faster than mass. The Menopause Society points out that women naturally lose 3 to 8% of their muscle mass per decade after age 30.

Osteoporosis Canada also recommends strength exercises at least twice a week. Losing weight after 40 looks at what changes with age.

05How much to aim for each week

The Canadian 24-Hour Movement Guidelines recommend muscle-strengthening activities using major muscle groups at least twice a week for adults aged 18 to 64; the U.S. guidelines call for working all major muscle groups on 2 or more days a week.

The American College of Sports Medicine adds, in its 2011 position stand: each major muscle group 2 to 3 days a week, with 48 hours of rest between sessions for the same group, and 10 to 15 repetitions to begin with. These are benchmarks for a healthy adult; with a health condition, adapt them with your doctor.

06Joanie's classes, for strength

Joanie Roussy's women's classes, at noon on weekdays, make strength part of the program. Strong Nation™ syncs every cardio and strength move to the music, for 45 minutes, with no equipment; Bootcamp moves you from station to station, with and without equipment; Zumba® gets you moving to music. For a specific goal, Joanie also offers private, personalized 60-minute training sessions on request, with training plans available. Adult karate, mixed and open from age 14, also builds strength.

07On the island itself

For people who live on Nuns' Island, the René-Lévesque path is good for walking on days without class, and the dojo is right on the island, at 550 chemin du Golf, suite 010. From elsewhere, getting to the dojo works out the route; the schedule gives the class days.

Good to know. This guide informs; it does not replace your doctor's advice. If you have an injury, pain, a health condition or are pregnant, talk to a physiotherapist or your doctor before starting strength training. Start gently, and stop any exercise that hurts.

Sources

  1. Barakat et al., “Body Recomposition”, Strength and Conditioning Journal (2020) — doi.org/10.1519/SSC.0000000000000584
  2. Donnelly et al., American College of Sports Medicine position stand, Med Sci Sports Exerc (2009) — doi.org/10.1249/MSS.0b013e3181949333
  3. Obesity Canada, chapter “Physical Activity in Obesity Management” (2020) — obesitycanada.ca/wp-content/uploads/2020/08/Physical-Activity-in-Obesity-Management.pdf
  4. Mitchell et al., Frontiers in Physiology (2012) — frontiersin.org/articles/10.3389/fphys.2012.00260/full
  5. The Menopause Society, “MenoNote: Midlife Weight Gain” (2025) — menopause.org/wp-content/uploads/for-women/MenoNote-Weight-Gain.pdf
  6. Osteoporosis Canada, “Too Fit To Fracture” (2024) — osteoporosis.ca/too-fit-to-fracture/
  7. CSEP, Canadian 24-Hour Movement Guidelines, adults 18–64 (2020) — csepguidelines.ca/guidelines/adults-18-64/
  8. Physical Activity Guidelines for Americans, 2nd edition (2018) — odphp.health.gov/sites/default/files/2019-10/PAG_ExecutiveSummary.pdf
  9. Garber et al., American College of Sports Medicine position stand, Med Sci Sports Exerc (2011) — doi.org/10.1249/MSS.0b013e318213fefb

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