Study Overview

• When: Study conducted from October 2023 to May 2024
• Purpose: To evaluate the effects of a 12-week resistance training program on muscle strength, physical function, neuropsychiatric symptoms, and muscle fiber size in women with Myotonic Dystrophy Type 1 (DM1).

Why the Researchers Studied This

DM1 is a genetic neuromuscular disorder that causes muscle weakness, pain, fatigue, and apathy, disproportionately affecting women. This study aimed to address the gap in research on the benefits of resistance training for women with DM1, as previous studies had focused primarily on men.

Who the Researchers Studied

• Participants:
  • 12 women with DM1, aged 20-60, recruited from Quebec, Canada.
  • Cohort characteristics: Average age 37.3 years; majority exhibited juvenile or adult-onset DM1 symptoms.
  • Completion Rate: 11 participants completed the program with an average attendance rate of 98.5%.

What Methods or Interventions Were Used

• Training Program:
  • A 12-week, supervised resistance training program focused on the lower limbs.
  • Exercises included squats, leg presses, hip abductions, knee extensions, and plantar flexions, performed twice weekly with progressive overload.
  • Each session began with a 5-minute warm-up, followed by three sets of 6–8 repetitions for each exercise.
• Assessments:
  • Strength tests (1-repetition maximum and isometric measurements).
  • Functional mobility tests (e.g., timed stair climbing, sit-to-stand tests).
  • Neuropsychiatric evaluations (e.g., apathy and depression scales).
  • Muscle biopsies to analyze fiber size and composition.

What Was Found

1. Muscle Strength Gains:
   • Significant increases in lower limb strength (e.g., hip and knee extensors).
   • 1-repetition maximum strength improved across all exercises.
2. Functional and Physical Improvements:
   • Enhanced performance in the sit-to-stand test.
   • Pain interference in daily activities decreased significantly.
3. Neuropsychiatric Benefits:
   • Apathy scores improved by 9%, with gains sustained up to six months post-intervention.
   • Depression symptoms decreased significantly during the program.
4. Muscle Adaptations:
   • Muscle fiber size increased by 9%, particularly in type I fibers.

Why This Matters

The study demonstrates that resistance training is a safe, effective, and multidimensional therapy for women with DM1. It improves physical strength, mobility, and mental well-being while addressing key disease symptoms such as apathy and pain.

Takeaway

Resistance training offers a valuable therapeutic option for managing DM1 symptoms in women. The findings support its integration into personalized care plans to enhance strength, mobility, and quality of life.

Reference for Further Reading
Girard-Côté, L., Gallais, B., Gagnon, C., et al. (2024). Resistance training in women with myotonic dystrophy type 1: A multisystemic therapeutic avenue. Neuromuscular Disorders, 40(1), 38–51. https://doi.org/10.1016/j.nmd.2024.05.009.