An Exploratory Study of the Short-Term Association of Resistance Training With Circulating Inflammatory Biomarkers,...

Systemic low-grade inflammation and subtle executive-function decline can emerge during midlife, yet short-term lifestyle approaches remain understudied. This single-arm interventional pre-post study examined whether a 4-week supervised resistance-training program was associated with changes in circulating inflammatory biomarkers, plasma brain-derived neurotrophic factor (BDNF), and executive-task performance in healthy midlife adults.

Five hundred healthy adults aged 50-65 years entered a supervised resistance-training program conducted three times weekly for 4 weeks after screening 647 individuals. Assessments were completed at baseline and 72 h after the final training session. Primary full-cohort outcomes included plasma interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), BDNF, two-back accuracy, two-back reaction time, Stroop interference, and Stroop accuracy. Adherence was recorded prospectively and summarized as ≥11 sessions (n = 312), 10 sessions (n = 146), and <10 sessions (n = 42). Full-cohort analyses were treated as the primary analyses, while per-protocol, adherence-stratified, and sensitivity analyses were reported as secondary analyses.

In the full analytic cohort, IL-6 decreased from 2.83 ± 1.60 to 2.09 ± 1.34 pg/mL, TNF-α decreased from 3.61 ± 1.07 to 3.12 ± 0.96 pg/mL, and BDNF increased from 23.4 ± 5.6 to 26.1 ± 6.2 ng/mL. The corresponding mean changes were -0.74 pg/mL for IL-6, -0.49 pg/mL for TNF-α, and +2.7 ng/mL for BDNF, with all paired comparisons statistically significant. Executive-task performance also improved, with two-back accuracy increasing from 83.7 ± 8.9% to 87.6 ± 7.2%, two-back reaction time decreasing from 690 ± 89 to 652 ± 82 ms, Stroop accuracy increasing from 89.8 ± 7.4% to 91.9 ± 6.2%, and Stroop interference decreasing from 238 ± 47 to 211 ± 41 ms. Secondary adherence-stratified analyses showed larger numerical biomarker and cognitive changes among participants completing ≥11 sessions, but these subgroup findings were interpreted descriptively because adherence groups were not randomized.

In healthy midlife adults, a 4-week supervised resistance-training program was associated with lower circulating IL-6 and TNF-α, higher plasma BDNF, and modest improvement in working-memory and inhibitory-control performance. These findings reflect within-cohort pre-post associations rather than comparative efficacy and should be interpreted cautiously because of the single-arm design, absence of central biomarkers, and short follow-up duration.