The Case For Doing Both: Why "Overall Training" Outperforms Specialization
A truth most fitness writing avoids: most people who lift don’t do cardio, and most people who do cardio don’t lift. Each group has reasons. Each group is leaving measurable health on the table.
In 2022, a paper published in JAMA Internal Medicine (Gorzelitz et al.) looked at adults who met both the aerobic and the muscle-strengthening physical activity guidelines and compared them to adults who met only one — or neither. The combined-modality group had a 47% lower risk of all-cause mortality compared to the inactive group. The single-modality groups had 25–32% reductions. The combination didn’t just add up. It multiplied.
Figure reference: Gorzelitz J et al., “Independent and joint associations of weightlifting and aerobic activity with all-cause, cardiovascular disease and cancer mortality.” Br J Sports Med. 2022;56(22):1277–1283. PMID: 36167669. Reference Figure 2: hazard ratios for combined vs. single modalities.
The mechanism for this combination is not mysterious. Cardio improves the cardiovascular delivery system. Strength training preserves the muscle that does the work. Each fixes a problem the other can’t reach.
Why we self-sort into one mode
People settle into one type of training for the same reason they settle into one type of food: it’s what feels familiar. A lifter who tried running once and felt slow goes back to the squat rack. A runner who tried lifting once and felt awkward goes back to the trail. The thing they didn’t try long enough to adapt to feels permanently off-limits.
This sorting becomes a problem in middle age. Lifters in their forties who never built cardiorespiratory fitness start to feel the staircase. Runners in their forties who never built muscle start to lose lean mass at roughly 1% per year, accelerating after 50. The single-mode trap costs you in the second half.
How to combine them without overtraining
The classic objection to combined training is the “interference effect” — the idea that endurance work blunts strength adaptations. This effect is real but smaller than commonly believed. A 2022 meta-analysis in Sports Medicine (Schumann et al.) found the interference was meaningful primarily when training volume was very high in both modalities simultaneously. At normal training doses for a working adult — two to three strength sessions, two to three cardio sessions per week — the interference was negligible.
A reasonable weekly structure for most clients: Monday strength (full-body or upper); Tuesday zone-2 cardio, 40–60 minutes; Wednesday strength (full-body or lower); Thursday short intervals, 20–25 minutes; Friday optional third strength session, lighter; Saturday longer slow cardio or hike, 60–90 minutes; Sunday rest or walking.
That’s five training sessions plus weekend movement. It fits inside the lives of every BTZ client I’ve programmed it for — including parents of young children, surgeons, and pilots.
The metabolic case
In a 2023 paper I co-authored (Muñoz, Botezelli, et al., Cellular and Molecular Life Sciences), we directly compared endurance and resistance training in mice with reduced GLUT4 expression — a model of impaired glucose handling. Both modalities improved insulin signaling in muscle, but through different intracellular pathways. Strength worked through the Akt pathway. Endurance worked through AMPK. The combination produced compounding effects on insulin sensitivity that neither alone could achieve.
This is the molecular evidence for what the JAMA cohort study saw at the population level.
This article is educational and is not medical advice. Diego Botezelli is a researcher and coach, not a physician — he does not diagnose, treat, or prescribe. Talk to your doctor before changing medication, supplements, or training, especially if you have a health condition or take prescription drugs.
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Every program is periodized from the same literature this article cites, then adjusted to your body composition, your schedule and your training history.
