ORIGINAL ARTICLE Jyrki A. Kettunen á Urho M. Kujala á Heli RaÈty Seppo Sarna Jumping height in former elite athletes Accepted: 1 September 1998 Abstract To evaluate lower-limb explosive strength with respect to lifetime athletic activity, we measured vertical jumping height on a contact mat in former male runners (n  28), soccer players (n  31), weightlifters (n  29) and shooters (n  29) (age range 45±68 years). There were no statistically signi®cant age-adjusted sport-group dierences in jumping height, but dierences by sport were evident among the subgroup of athletes without hip or knee osteoarthritis (n  65) (P < 0.05). Thus, sports that increased jumping height also predisposed to lower- limb osteoarthritis. After adjustment for age and sport, the subjects without osteoarthritis jumped higher than those with osteoarthritis (n  33) (P < 0.01). In a mul- tiple linear regression analysis, age, reported hip and knee disability, and knee pain reduced jumping height. Hours spent in team-training during the past 12 months and the hours spent during their lifetime in power training were associated with improved vertical jumping height and together explained 41% of the dierence among the sub- jects. The ability to jump even among athletes with hip or knee osteoarthritis would suggest that former elite ath- letes possess advanced lower limb muscle function. Key words Knee á Hip á Sports á Osteoarthritis á Explosive strength Introduction The importance of life-long physical activity for lower limb function is controversial. Exercise-related physical loading can predispose to osteoarthritis (OA) of weight- bearing joints. In particular, hip and knee OA have been reported among former team game and power sport athletes (KluÈnder et al. 1980; Lindberg et al. 1993; Kujala et al. 1994a 1995), but the risk has not been found to be equally elevated in former endurance ath- letes (Kujala et al. 1994a). Old active male subjects have been found to develop higher isometric knee-extension forces than do their population sample controls (SipilaÈ et al. 1991) and those with greater isometric strength also demonstrate a higher maximal walking speed (Rantanen et al. 1994). In old age, members of a runners' club have been shown to have better lower-extremity function than do their community controls (Fries et al. 1994). Among healthy subjects from the general population, physically active old subjects are usually stronger than inactive controls, and lower-limb muscle strength has a favourable eect on their mobility. Among former elite athletes the bene®ts on mobility of lower-limb muscle strength versus the adverse eect of hip or knee OA are unknown. The aim of this study was to investigate jumping height among former elite athletes from dierent sports, taking into account the possible development of hip or knee OA. We selected former top- level athletes in sports which diered in the long-term loading on hip and knee joints and training of the muscles. The four study groups included former long-distance runners, soccer players, weightlifters and shooters. Methods Subjects We identi®ed male athletes who had participated at least once in the Olympic, World or European championships, or in intercoun- try competitions between 1920 and 1965 (Sarna et al. 1993). In 1985, a questionnaire on health and life-style was mailed to all such surviving athletes. Respondents who in 1992 were aged 45±68 years including all the shooters (n  35) and runners (n  38), as well as a sample of the soccer players (n  37) and weightlifters (n  37), who were of comparable age and occupation, were in- vited to participate in the study. Of the total 117 (80%) agreed to participate including 28 runners, 31 soccer players, 29 weightlifters and 29 shooters (Table 1). Interviews, clinical examinations and Eur J Appl Physiol (1999) 79: 197±201 Ó Springer-Verlag 1999 J.A. Kettunen (&) á U.M. Kujala á H. RaÈty Unit for Sports and Exercise Medicine, Institute of Biomedicine, University of Helsinki, Mannerheimintie 17, ToÈoÈloÈ Sports Hall, FIN-00250, Helsinki, Finland S. Sarna Department of Public Health, University of Helsinki, Helsinki, Finland