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Jul 8, 2026, 11:30 PM CUT

Sienna Miller Explains Rebuilding Muscles With Specific Workouts at 44

Sienna Miller, the British actor, recently became the mother of her third baby, her second with her boyfriend, Oli Green.

But before her delivery of her third baby in May, Miller’s trainer, Matt Bevan, with whom she spent a year building a useful fitness routine, developed a routine for her that helped her stay fit.

However, according to Women's Health, Matt recently shared that the mom of 3 is currently focusing on building her muscle.

Matt told Women's Health they train “three to four times a week, depending on how close she is to attending a big event. We train mostly in person, but also online when she’s traveling”.

@mattbevan_ vi Instagram

@mattbevan_ vi Instagram

Miller's current goal is to build some muscle, but according to her trainer, they are trying to stay consistent with 3 sessions per week.

He added, “From there, we adapt her workouts based on how fatigued she is and how well she’s slept with a new baby”.

Matt later shared the 45-minute each begginer and intermediate level workout routine by Miller to build strength and muscle.

Sienna Miller's Beginner-Level Workout

It consists of 3 rounds with 60-90 secs resting between rounds.

After warming up, Miller follows movements such as:

  • B-stance wall-supported Romanian deadlift: 10-12 reps
  • Modified side plank with Pilates ball squeeze: 12 reps each side
  • Glute-focused step-ups: 10-15 reps
  • B-stance dumbbell hip thrust:12-20 reps
  • Bird dog dumbbell row: 12 rows each side
  • Walking lunges: 10-12 reps
  • Crossover cable Y-raise:10 reps
  • Cable woodchop: 8 reps each side.

Miller's Intermediate-advanced-level Workout

Her intermediate to advanced strength workout, includes exercises such as:

  • Deficit sumo dumbbell Romanian deadlift: 12 reps
  • Pull-ups with slow lower: 6 reps
  • Bulgarian split squat with dumbbell: 10 reps
  • Hip thrusts: 20 reps then 5 breath rest and then as many reps possible
  • One-arm Hollow hold with dumbbell press: 12 reps each side
  • Mat sit-ups: 15 reps
  • One-arm cable overhead tricep extension: 15 reps
  • Glute cable kick back with bench support: 20 reps each side.

Which exercises do you regularly perform in your training regimen? Comment below.

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Written by

Supradeep Dutta

Edited by

Ashvinkumar Patil