Alternative Physical Activity Strategies for Breast Cancer Survivors (PACE)

Alternative Physical Activity Strategies for Breast and Prostate Cancer Survivors

The primary aim of this study is to compare the acute glycemic effects of two novel, alternative physical activity (PA) strategies (dispersed post-meal PA, PA snacks) to a no PA condition and to exercise sessions representing the PA guidelines (standard 30-minute walking bout performed under fasting and under postprandial conditions and a standard 30-minute resistance training session) among sedentary breast cancer survivors who are currently receiving hormone therapies and age- and BMI-matched postmenopausal women without a history of cancer. The secondary aim is to determine whether the alternative PA strategies are acceptable and feasible in the free-living setting. An exploratory aim is to determine whether the outcomes differ between women with and without a history of breast cancer and use of aromatase inhibitors.

The investigators hypothesize that:

1. Dispersed PA and PA snacks will result in greater reductions in 24-hour glucose and postprandial glucose compared to the no-PA baseline and similar reductions to a standard 30-minute bouts of walking;
2. The alternative PA strategies will be more feasible and have greater acceptability by cancer survivors compared to the standard 30-minute bout of walking or resistance training; and
3. The different PA strategies will have similar effects on glycemic outcomes for both breast cancer survivors and cancer-free controls. The resistance exercise session is an exploratory trial as the effects of it on acute glycemic control are understudied.

Study Overview

• Status: Recruiting
• Conditions: Breast Cancer; Insulin Resistance; Cardiometabolic Risk Factors
• Intervention / Treatment: Behavioral: Standard Physical Activity - Fasted; Behavioral: Standard Physical Activity - Post-Meal; Behavioral: Dispersed Physical Activity; Behavioral: Physical Activity Snacks; Behavioral: Muscle Strengthening

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Amy A Kirkham, PhD; Phone Number: 416-946-4069; Email: amy.kirkham@utoronto.ca
• Study Contact Backup: Name: Jenna B Gillen, PhD; Phone Number: 416-978-3244; Email: jenna.gillen@utoronto.ca

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada
      • Recruiting
      • Remote Ontario-wide
      • Contact: Amy A Kirkham, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Postmenopausal biological females diagnosed with stage I, II, or III breast cancer and currently using aromatase inhibitors (AI) for at least 3 months prior to start of study participation

• All participants must meet the following criteria:

  • Body mass index equal to or greater than 25 kg/m^2.
  • Self-report consuming three main meals daily.
  • Self-report as being sedentary (i.e., less than 30 minutes/week of moderate-to-vigorous aerobic physical activity and less than twice/week muscle strengthening of major muscle groups in the last three months.

Exclusion Criteria:

• If unable or unwilling to receive medical clearance by a physician after being screened for major signs or symptoms of cardiovascular diseases, diabetes, or renal disease and safety to initiate exercise.

  • Major signs or symptoms of cardiovascular diseases, diabetes, or renal disease are taken from the American College of Sports Medicine's Guidelines for Exercise Testing and Prescription 11th edition Table 2.1. They include pain or discomfort in the chest, neck, jaw, arms with rest or exercise, shortness of breath at rest or with mild exertion, dizziness or syncope, ankle edema, palpitations or tachycardia, intermittent claudication, known heart murmur, and unusual fatigue with usual activities.
  • Safety to initiate exercise will be screened using the Get Active Questionnaire, which is the Canadian Society of Exercise Physiology's endorsed evidence-based pre-screening tool.
• Using drugs for diabetes management (e.g., exogenous insulin, Ozempic, metformin, etc.) or actively losing weight (i.e., >5 kg weight loss in past 3 months) from drugs or other reasons
• Report any injury or other reason for not feeling capable of completing a 30 minute continuous walk or muscle strengthening exercise
• Unable to access an Ontario Lifelabs location for an overnight fasted blood draw
• Do not have a smartphone compatible with the applications required to collect data.
• Cannot read and understand the consent form or communicate in English.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Standard Physical Activity - Fasted; Participants will perform 30 minutes of walking at a self-selected pace 15 minutes prior to consumption of first meal in the morning (including cream/sugar/milk in coffee or tea).	Behavioral: Standard Physical Activity - Fasted; 30 minutes of walking at a self-selected pace that they must have completed 15 minutes prior to consumption of first meal in the morning.
Experimental: Standard Physical Activity - Post-Meal; Participants will perform 30 minutes of walking at a self-selected pace 30 minutes after the start of the first meal in the morning.	Behavioral: Standard Physical Activity - Post-Meal; 30 minutes of walking at a self-selected pace to start 30 minutes after the start of the first meal in the morning.
Experimental: Dispersed Physical Activity; Participants will perform 10 minutes of walking at a self-selected pace 30 minutes after the start of each main meal throughout the day (i.e., three bouts total).	Behavioral: Dispersed Physical Activity; 10 minutes of walking at a self-selected pace to start 30 minutes after the start of each main meal throughout the day (i.e., three bouts total).
Experimental: Physical Activity Snacks; Participants will perform 2 minutes of walking or marching on the spot at a self-selected pace every 30 minutes throughout the day for 7.5 waking hours.	Behavioral: Physical Activity Snacks; 2 minutes of walking or marching on the spot at a self-selected pace every 30 minutes throughout the day for 7.5 waking hours.
Experimental: Muscle Strengthening; Participants will perform 30 minutes of muscle strengthening exercises targeting the major muscle groups of the whole body performed by following along with a video, to start 30 minutes after the start of the first meal in the morning.	Behavioral: Muscle Strengthening; 30 minutes of muscle strengthening exercises targeting the major muscle groups of the whole body, to start 30 minutes after the start of the first meal in the morning.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
24-hour glucose incremental area under the curve (iAUC)	Assessed for each single-day intervention using a continuous glucose monitor from 8:00 am to the intervention day to 8:00 am the following morning.	Baseline, 24 hours of each intervention day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
24-hour mean glucose	Assessed for each single-day intervention using a continuous glucose monitor from 8:00 am to the intervention day to 8:00 am the following morning.	Baseline, 24 hours of each intervention day
Postprandial iAUC	Assessed for each single-day intervention using a continuous glucose monitor for two hours following each meal.	Baseline, 24 hours of each intervention day
Peak postprandial glucose	Assessed as the highest glucose concentration during the 2 hours following each meal using a continuous glucose monitor.	Baseline, 24 hours of each intervention day
Daytime glucose concentration	Assessed for each single-day intervention using a continuous glucose monitor from 6:00 am to 12:00 am on the intervention day.	Baseline, 24 hours of each intervention day
Nocturnal glucose concentration	Assessed for each single-day intervention using a continuous glucose monitor from 12:00 am to 6:00 am on the intervention day.	Baseline, 24 hours of each intervention day
Time in hypoglycemia	Assessed as the number of hours with glucose less than 3.9 mmol/L using a continuous glucose monitor.	Baseline, 24 hours of each intervention day
Time in hyperglycemia	Assessed as the number of hours with glucose greater than 10 mmol/L using a continuous glucose monitor.	Baseline, 24 hours of each intervention day
Indices of glycemic variability	Indices include standard deviation, coefficient of variation, mean amplitude of glycemic excursion, and continuous overall net glycemic action	Baseline, 24 hours of each intervention day
Participant acceptability	Acceptability related to participants' experience with each single-day intervention will be assessed using a researcher-developed questionnaire at the end of each intervention day. Seven items use a 5-point Likert scale with responses ranging from "Strongly Disagree" to "Strongly Agree", while four items ask about participant confidence with responses ranging from 0 ("Not Confident") to 10 ("Very Confident). A higher total score indicates the intervention is more acceptable to the participant.	24 hours of each intervention day
Participant enjoyment	Enjoyment related to participants' experience with each single-day intervention will be assessed using the short form of the Physical Activity Enjoyment Scale at the end of each intervention day, consisting of 8 items each scored on a 7-point Likert scale, with the total score ranging from 8 to 56, and a higher total score indicating greater enjoyment.	24 hours of each intervention day

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physical activity	Participants will be asked to wear a Garmin smartwatch for the duration of the study to track completion of physical activity bouts and heart rate during each bout for each single-day intervention	24 hours of each intervention day
Systolic and Diastolic Blood Pressure	Measured as the average of the last 5 of 6 systolic and diastolic blood pressure measurements using an automatic blood pressure device.	Baseline
Waist circumference	Circumference of the waist measured using an inelastic tape	Baseline
Body mass index (BMI)	Calculated using self-reported body weight and height.	Baseline
Fasting glucose	Analyzed from fasted (overnight, 12 hours) venipuncture performed and processed at any Lifelabs location of participant's choice.	Baseline
Fasting insulin	Analyzed from fasted (overnight, 12 hours) venipuncture performed and processed at any Lifelabs location of participant's choice.	Baseline
Lipid profile: HDL, LDL, total cholesterol, triglycerides	Analyzed from fasted (overnight, 12 hours) venipuncture performed and processed at any Lifelabs location of participant's choice.	Baseline
Hemoglobin A1c	Analyzed from fasted (overnight, 12 hours) venipuncture performed and processed at any Lifelabs location of participant's choice.	Baseline
Metabolic syndrome	Determined based on standardized criteria using previously specified outcomes.	Baseline
Framingham 10-year cardiovascular disease risk score	Calculated via a standardized scoring algorithm using previously specified outcomes, with total scores ranging from less than -3 (indicating <1% 10-year risk of cardiovascular disease) to more than 21 (indicating >30% 10-year risk of cardiovascular disease).	Baseline
Dietary intake	Various components of dietary intake including macronutrients and micronutrients will be assessed through 1-day food record on a weekday collected using ASA-24 online system.	Baseline
Perceived stress	Assessed using a researcher-developed visual analog scale (0-100, with a higher value indicating greater perceived stress) at the start of each intervention day.	Prior to start of each intervention
Muscle soreness	Assessed using a researcher-developed visual analog scale (0-100, with a higher value indicating greater muscle soreness) at the start of each intervention day.	Prior to start of each intervention
Sleep quantity and quality	Measured via Garmin smartwatch for the total sleep duration and efficiency.	Baseline, 24 hours of each intervention day

Collaborators and Investigators

• Sponsor: University of Toronto

Study record dates

Study Major Dates

• Study Start (Actual): October 22, 2024
• Primary Completion (Estimated): April 30, 2026
• Study Completion (Estimated): July 1, 2026

Study Registration Dates

• First Submitted: September 13, 2024
• First Submitted That Met QC Criteria: October 7, 2024
• First Posted (Actual): October 9, 2024

Study Record Updates

• Last Update Posted (Actual): December 2, 2025
• Last Update Submitted That Met QC Criteria: November 24, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Physical Activity; Hormone Therapy; Glycemic Control
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Metabolic Diseases; Glucose Metabolism Disorders; Skin Diseases; Breast Diseases; Hyperinsulinism; Behavior; Nutritional and Metabolic Diseases; Skin and Connective Tissue Diseases; Breast Neoplasms; Insulin Resistance; Motor Activity
• Other Study ID Numbers: REB #44269

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No