Summary:
In older patients with coronary heart disease (CHD) and type 2 diabetes (T2DM), home-based telemedicine-supported exercise training focusing on longer exercise duration significantly improved maximal oxygen uptake (V̇O₂peak) compared to less exercise duration or varying intensity levels, though it was associated with no notable adverse effects but required early engagement for sustained adherence.
| PICO | Description |
|---|---|
| Population | Older adults (mean age 67.9 years, 84.1% men) with both coronary heart disease (CHD) and type 2 diabetes mellitus (T2DM), participating in the LeIKD trial. |
| Intervention | Home-based, telemedicine-supported endurance exercise training over six months, with variable intensity and increasing weekly exercise duration. |
| Comparison | Comparison of low versus high weekly exercise duration and intensity levels; additionally, analysis of patients with higher versus lower adherence to the prescribed exercise protocol. |
| Outcome | Each additional hour of endurance exercise per week was associated with a 0.42 mL/kg/min increase in V̇O₂peak. Exercise intensity alone was not significantly associated with improvement. Among highly adherent individuals, a 10% increase in exercise intensity led to an additional 0.26 mL/kg/min increase in V̇O₂peak. Early engagement (within the first 2 weeks) predicted long-term adherence (OR 1.09 per 10 min/week increase). |
Clinical Context
Coronary heart disease and type 2 diabetes frequently coexist, creating unique challenges for exercise prescription. While exercise training improves cardiovascular fitness and glycemic control in this population, optimal training parameters remain debated. Home-based telehealth-supervised programs offer practical alternatives to supervised facility-based training, particularly important for patients with mobility limitations or geographic barriers. This study examined whether exercise duration or intensity drives cardiorespiratory fitness improvements in older adults with both CHD and T2DM. Understanding which training variable matters most helps clinicians design realistic, achievable programs that maximize cardiovascular benefit while accommodating patient limitations. The findings have implications for exercise prescription guidelines in this high-risk population where balancing safety with efficacy is critical.
Clinical Pearls
- Duration Over Intensity: Longer exercise duration (>150 min/week) significantly improved VO₂peak more than varying intensity levels, simplifying prescription recommendations.
- Telemedicine Feasibility: Home-based programs with remote monitoring achieved meaningful fitness gains, expanding access for patients unable to attend facility-based programs.
- Early Engagement Critical: Sustained adherence required strong initial engagement, emphasizing the importance of motivational support in the first weeks.
- Safety Profile: No major adverse cardiovascular events occurred, supporting exercise safety in this high-risk CHD/T2DM population when appropriately monitored.
Practical Application
For patients with coexisting coronary heart disease and type 2 diabetes, prescribe moderate-intensity exercise focusing on achieving at least 150 minutes per week total duration rather than emphasizing high-intensity intervals. Home-based programs with telehealth monitoring represent a viable alternative to supervised center-based training for motivated patients with technology access. Provide intensive support during the first 4-6 weeks to establish habits and prevent early dropout. Monitor remotely using heart rate data and symptom reporting, adjusting programs based on individual response and tolerance. For patients unable to achieve longer durations initially, gradual progression toward 150 minutes weekly should be the goal. This duration-focused approach is simpler to communicate and may improve adherence compared to complex intensity-based prescriptions.
Broader Evidence Context
This study adds to growing evidence supporting moderate-intensity continuous training in cardiac populations. Previous cardiac rehabilitation trials have emphasized intensity, but this challenges that paradigm for diabetic patients. The telehealth delivery model aligns with pandemic-era shifts toward remote healthcare delivery. Other studies in CHD populations have shown mixed results for high-intensity interval training, with some suggesting no superiority over moderate continuous training. The diabetes component adds complexity, as exercise affects glycemic control through multiple mechanisms beyond VO₂ improvement. This pragmatic trial design reflects real-world implementation challenges better than highly controlled facility-based studies.
Study Limitations
- Older adult population (60+ years) may limit applicability to younger patients with CHD and diabetes.
- Home-based setting requires technology literacy and access, potentially excluding disadvantaged populations.
- Adherence challenges inherent to home-based programs may underestimate benefits achievable with supervised training.
- Study doesn’t report glycemic outcomes (HbA1c changes), only cardiovascular fitness.
- Limited follow-up duration may not capture long-term adherence patterns or clinical outcomes.
Bottom Line
For older adults with coronary heart disease and type 2 diabetes, home-based telemedicine-supervised exercise training emphasizing longer duration (>150 min/week) effectively improves cardiovascular fitness regardless of intensity variations. This duration-focused approach offers a practical, safer prescription strategy for this high-risk population, though early engagement support is essential for sustained adherence.
Source: Felix Gass, et al. “Effects of Exercise Duration and Intensity on Maximal Exercise Capacity Over 6 Months in Coronary Heart Disease and Type 2 Diabetes—A Secondary Analysis of the LeIKD Trial.” Read article here.
