Effects of moderate and high intensity exercise on T1/T2 balance
Guanggao Zhao, Shi Zhou, Allan J Davie, Quansheng Su · 2026 · 105 citationsRead the paper
Type 1 (TI) and Type 2 (T2) lymphocytes promote cell-mediated immunity and humoral immunity respectively. Evidence accumulated over the past two decades has demonstrated diverse responses of T1 and T2 cells to acute exercise or long-term training at moderate and high intensities. This brief review highlights the current findings from animal and human experimental models on the relationship between the T1 and T2 cell counts and the cytokines these cells produce, in response to moderate and high intensity exercise. The potential of using the T1/T2 balance as an indicator of immune function changes in response to exercise is discussed.
What the full text shows
Shown in the lab- High intensity exercise favors the type 2 phenotype T cells, contributing to down-regulation of host protection against viral infections. (General human/animal models)
- Moderate intensity chronic exercise shifts the T1/T2 balance toward type 1 in older adults, reversing age-associated T1 reduction. (Older adult humans)
- Moderate intensity chronic walking increases the Th1/Th2 and Tc1/Tc2 ratios. — two-fold increase in Th1/Th2 ratio (Older adult humans, 4 years of walking (3-5 km daily, 10 km weekly))
- Moderate intensity chronic cycling and resistance training increases Th1 and decreases Th2 cells. (Older adult humans, 6 months of training)
- Acute high intensity treadmill exercise decreases Th1 and Tc1 cells. (Endurance-trained male runners, 75% VO2max, 2.5 h duration)
- Moderate intensity chronic treadmill training improves T1 and T2 cell function in clearing HSV-1. (Young and older adult mice, 8 weeks training)
- Setup
- Various cohorts including young/older adult mice and young/older adult humans across acute and chronic exercise protocols.
- How
- Review of existing animal and human experimental models analyzing T cell counts and cytokine production (IFN-γ, IL-2, IL-4, IL-10) in response to exercise.
- Limitations
- Inconsistency between cytokine production levels and the number of cells expressing those cytokines in short recovery periods. · Lack of experimental data on the effect of moderate intensity exercise on T2 cell function. · Small number of available experiments for some conclusions.
Summarized by Gemma 4 from the open-access full text · 11 Oct 2026. Read it