Lymphocyte, NK and LAK cell responses to maximal exercise

Area of Science:

• Exercise immunology
• Sports science
• Human physiology

Background:

• Maximal exercise is known to induce significant physiological stress.
• The impact of intense, prolonged exercise on immune system function requires further investigation.

Purpose of the Study:

• To determine if exhaustive exercise, specifically a six-minute maximal rowing bout, suppresses the immune system during the recovery period.
• To analyze changes in various immune cell populations and functions following intense exercise.

Main Methods:

• Ten healthy male oarsmen completed a six-minute maximal effort rowing exercise.
• Blood samples were collected pre-exercise, immediately post-exercise, and two hours post-exercise.
• Analyzed were leukocyte counts (lymphocytes, monocytes, neutrophils), T cells (CD3+, CD4+, CD8+), B cells (CD19+), natural killer (NK) cells (CD16+), lymphokine-activated killer (LAK) cell activity, and mononuclear cell (BMNC) proliferation.

Main Results:

• Leukocyte, neutrophil, and lymphocyte counts increased during exercise, with lymphocytes decreasing below pre-exercise levels two hours post-exercise.
• T cells (CD3+, CD4+, CD8+), B cells (CD19+), and NK cells (CD16+) increased during exercise, with CD3+ and CD8+ decreasing below pre-exercise levels two hours post-exercise.
• NK and LAK cell activities increased during exercise and returned to baseline levels two hours post-exercise, while mononuclear cell proliferative responses remained unchanged.

Conclusions:

• Six-minute maximal exercise involving large muscle mass does not appear to suppress the immune response during the initial recovery phase.
• Immune cell activity, particularly NK and LAK cell functions, recovers to baseline levels within two hours post-exercise.
• Further research is needed to understand the long-term immune effects of different exercise intensities and durations.