Plyometric Strength-Endurance Exercise in Breast Cancer

Official title

Therapeutic Plyometric-Based Strength-Endurance Exercise Program for Breast Cancer Patients and Survivors to Improve Quality of Life and Physical and Mental Function

Overview

This study aims to compare an adapted plyometric strength-endurance exercise program with conventional strength training in women who are breast cancer survivors or currently undergoing treatment and who participate in provincial support associations. The goal is to determine whether a targeted plyometric intervention can provide additional benefits in physical and mental health outcomes. Using a cluster-randomized clinical trial design, the study will assess indicators such as functional capacity, muscle strength, fatigue levels, symptoms related to lymphedema, and overall quality of life. The findings are expected to contribute to a better understanding of how structured exercise programs can support recovery, physical function, and well-being in women affected by breast cancer.

Detailed description

Breast cancer is the most common malignancy among women worldwide. Despite significant advances in diagnosis and treatment that have improved survival rates, many patients and survivors continue to experience physical and psychological impairments that negatively affect their quality of life. Historically, intense or repetitive upper-limb exercise was discouraged due to concerns about triggering or worsening lymphedema. However, current evidence supports supervised therapeutic exercise as both safe and effective for this population. Strength training, in particular, has demonstrated benefits in muscle mass, physical function, bone health, fatigue reduction, and emotional well-being.

Most existing research has focused on conventional strength training programs, leaving a gap in the evidence regarding more dynamic approaches, such as strength-endurance training involving plyometric exercises. Research on plyometrics within oncology remains limited and has been conducted primarily in pediatric populations, such as survivors of childhood leukemia or children with neurofibromatosis type 1. Nevertheless, plyometric training-traditionally used in athletic performance and in patients with neurological or musculoskeletal conditions-may offer significant therapeutic potential for women living with or recovering from breast cancer.

Plyometric exercises are known to enhance muscular power, balance, proprioception, and neuromuscular control, all of which are essential for restoring functional capacity and independence. Their dynamic, progressive nature may also support greater motivation and adherence, potentially translating into improvements in mental health, self-esteem, and body image.

In summary, plyometric-based strength-endurance training represents an innovative and promising approach to improving quality of life, functional performance, and overall well-being in women who are survivors of breast cancer or currently undergoing treatment. This study aims to address the existing evidence gap by evaluating the therapeutic effects of an adapted plyometric program compared with conventional strength training within a controlled clinical trial framework.

Interventions

• Other Plyometric Strength-Endurance Training
  Participants in the experimental group will take part in an adapted plyometric strength-endurance training program delivered through supervised 60-minute sessions, twice per week, over a 12-week period (24 sessions total). A minimum rest interval of 48 hours will be maintained between sessions. The frequency and duration of the intervention follow the recommendations of the National Strength and Conditioning Association (NSCA) for safe implementation of plyometric and strength-endurance exercise
• Other Conventional Strength Training
  Participants assigned to the control group will perform a conventional strength training program. This program has been designed as an active and structured intervention to allow a meaningful comparison with the effects of the plyometric training implemented in the experimental group. The exercise circuit will include functional movements aimed at global strengthening, with an emphasis on multi-joint patterns that promote transfer of improvements to activities of daily living.

Primary outcome measures

• Quality of life (Breast Cancer-Specific Quality of Life) [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]

Secondary outcome measures (12)

• Cardiorespiratory capacity [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Cancer-related fatigue [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Mobility and range of motion [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Muscle strength [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Proprioception [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Upper limb functionality [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Presence of lymphedema [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Sleep quality [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Kinesiophobia [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Enjoyment of physical activity [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Exercise adherence rate [Time frame: From enrollment to the end of treatment at 12 weeks, followed by an additional 12-week follow-up period]
• Intervention acceptability [Time frame: To the end of treatment at 12 weeks]

Eligibility criteria

Inclusion criteria

• Women aged 18 years or older.
• Prior diagnosis of breast cancer.
• History of mastectomy, including unilateral procedures, total breast surgery, or breast-conserving surgery.
• Completion of postoperative chemotherapy or radiotherapy, when indicated.
• Absence of contraindications for physiotherapy or therapeutic exercise.
• Willingness to voluntarily participate in the study.
• Ability to understand and sign the informed consent form.
• Availability to participate in the training program for the entire intervention period (approximately 12 weeks).

Exclusion criteria

• Participants will be excluded if any of the following conditions are present:
• Active metastasis to other organs or tissues (e.g., liver, kidney, lung, brain) or stage IV cancer that prevents safe participation in the therapeutic exercise program.
• Current diagnosis of cardiovascular, respiratory, neuromuscular, or musculoskeletal diseases that contraindicate physical exercise or impair safe completion of the program.
• Major surgery within the previous 6 months without medical clearance to resume physical activity.
• Cognitive impairment or mental health conditions that limit comprehension of instructions or safe engagement in the intervention.
• Current pregnancy.
• Lack of medical clearance for moderate-to-vigorous physical activity (as indicated by a medical certificate specifying the duration of the restriction and the conditions under which exercise may be resumed).

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Treatment

Study locations

Spain · 1 center

• Faculty of Physiotherapy — Pontevedra

Publications

• Paulo TRS, Rossi FE, Viezel J, Tosello GT, Seidinger SC, Simoes RR, de Freitas R Jr, Freitas IF Jr. The impact of an exercise program on quality of life in older breast cancer survivors undergoing aromatase inhibitor therapy: a randomized controlled trial. Health Qual Life Outcomes. 2019 Jan 18;17(1):17. doi: 10.1186/s12955-019-1090-4. PMID 30658629
• Breda SJ, Oei EHG, Zwerver J, Visser E, Waarsing E, Krestin GP, de Vos RJ. Effectiveness of progressive tendon-loading exercise therapy in patients with patellar tendinopathy: a randomised clinical trial. Br J Sports Med. 2021 May;55(9):501-509. doi: 10.1136/bjsports-2020-103403. Epub 2020 Nov 20. PMID 33219115
• Abd Elsabour AK, Zakaria HM, Fahmy EM, Khalil ASA, Alwhaibi RM, Ragab WM, Taha SI. Effect of Plyometric Exercises of Lower Limb on Strength, Postural Control, and Risk of Falling in Stroke Patients. Medicina (Kaunas). 2025 Jan 26;61(2):223. doi: 10.3390/medicina61020223. PMID 40005340
• Johnson BA, Salzberg CL, Stevenson DA. Effects of a plyometric training program for 3 children with neurofibromatosis type 1. Pediatr Phys Ther. 2012 Summer;24(2):199-208. doi: 10.1097/PEP.0b013e31824d30ee. PMID 22466394
• Elnaggar RK, Mahmoud WS, Abdrabo MS, Elfakharany MS. Effect of adaptive variable-resistance training on chemotherapy-induced sarcopenia, fatigue, and functional restriction in pediatric survivors of acute lymphoblastic leukemia: a prospective randomized controlled trial. Support Care Cancer. 2025 Feb 22;33(3):214. doi: 10.1007/s00520-025-09250-x. PMID 39985582
• Elnaggar RK, Mohamed RR. Aqua-Plyometric Exercises: Potential Implications for Bone Mineral Density, Functional Capacity, and Quality of Life in Survivors of Childhood Acute Lymphoblastic Leukemia. Semin Oncol Nurs. 2021 Dec;37(6):151225. doi: 10.1016/j.soncn.2021.151225. Epub 2021 Nov 6. PMID 34753640
• Ulrich G, Parstorfer M. Effects of Plyometric Versus Concentric and Eccentric Conditioning Contractions on Upper-Body Postactivation Potentiation. Int J Sports Physiol Perform. 2017 Jul;12(6):736-741. doi: 10.1123/ijspp.2016-0278. Epub 2016 Oct 13. PMID 27736266
• Lin Y, Wu C, He C, Yan J, Chen Y, Gao L, Liu R, Cao B. Effectiveness of three exercise programs and intensive follow-up in improving quality of life, pain, and lymphedema among breast cancer survivors: a randomized, controlled 6-month trial. Support Care Cancer. 2022 Dec 13;31(1):9. doi: 10.1007/s00520-022-07494-5. PMID 36512157

Identifiers

NCT: NCT07460492 · 2025/263 · 2025/001

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗