Beta-endorphin and components of depression as powerful discriminators between joggers and sedentary middle-aged men

• Published in: Journal of psychosomatic research Vol. 33; no. 3; pp. 293 - 305
• Main Authors: Lobstein, Dennis D., Rasmussen, Charles L., Dunphy, Gail E., Dunphy, Michael J.
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 1989
• Subjects: Adult; beta-Endorphin - blood; Biomarkers - blood; Depression - physiopathology; Humans; Jogging; Male; Middle Aged; MMPI; Physical Fitness; Stress, Psychological - physiopathology
• ISSN: 0022-3999; 1879-1360
• DOI: 10.1016/0022-3999(89)90020-2

This study identifies the relative importance of resting plasma beta-endorphin, used as a marker of perceived stress, and components of non-clinical depression that discriminate between physically active joggers and sedentary men. The profiles of joggers ( n = 10) and sedentary ( n = 10) middle-aged men (40–60 yr) were compared. The jogger had been running about 20 miles per week for at least 3 yr. Results: as expected, the joggers exhibited greater physical fitness, but lower circulating beta-endorphin (measured with the subjects at rest). The joggers also exhibited greater emotional stability (Eysenck scores), and lower depression (MMPI Scale 2 scores). In addition, the joggers had lower scores on MMPI subscales of depression: subjective depression, physical malfunctioning, mental dullness, and brooding. Multivariate discriminant function analyses showed that subjective depression, beta-endorphin, and physical malfunctioning were powerful discriminators between the jogger and sedentary groups. In conclusion: (1) subjective depression appeared to be the MMPI component of depression that most powerfully discriminated between joggers and sedentary middle-aged men in this study. (2) Lower beta-endorphin may be an adaptation to exercise training and was related to greater emotional stability and lower depression, especially lower subjective depression. (3) The lower beta-endorphin in the jogger group may be related to lower perceived stress in the joggers, relative to the sedentary group.