Does the effect of childhood physical fitness extend into adulthood? Dr. Benny Antony, MD, and colleagues at the University of Tasmania, Hobart, Tasmania, Australia, set out to answer this question in their latest research, published in the September issue of Arthritis Care & Research. For this 25-year cohort study, researchers specifically looked at how physical performance measures from child- and adulthood compared with adult knee joint tibial cartilage volume and tibial bone area.
This study, the Childhood Determinants of Adult Health Knee Study, used performance measures data on participants from two previous studies from 1985 and 2006. During both prior studies, participants’ performance measures were attained for physical work capacity at 170 heartbeats per minute, time taken on long and short runs, leg muscle strength and number of sit-ups completed.
During the current knee study, 330 participants (ages 31–41 years) from the previous studies underwent an MRI of their dominant knee. Tibial and patellar cartilage volumes were measured using 3-D imaging. Bone area was measured manually on T1-weighted fat-suppressed MR images.
After data analysis, researchers determined positive associations. Higher childhood heartbeat-based physical capacity was associated with greater adult cartilage volume, remaining significant after adjusting for tibial bone area and corresponding available adult fitness measures. “Suggesting childhood fitness affects adult knee structures independently of adult attained fitness,” write the authors.
Additionally, childhood heartbeat-based physical capacity measurements were positively associated with tibial cartilage volume, independent of similar adult measures, demonstrating a “great influence of environmental factors in the association of childhood fitness on adult cartilage volumes.”
The researchers found that all physical performance measures were also positively associated with tibial bone area.
The researchers conclude that childhood physical fitness, particularly heartbeat-based physical capacity, is important to adult knee structure and health. “The associations between fitness measures and tibial cartilage volume appear to be mediated in part by tibial bone area,” they write. “This suggests physical performance measures in childhood can independently influence adult knee joint structure, possibly through adaptive mechanisms during growth.”
Antony B, Jones G, Venn A, Blizzard L, Cicuttini F, March L, Cross M, Dwyer T, Ding C. Childhood physical performance measures and predictions of adulthood knee cartilage volume and bone area: A 25-year cohort study. Arthritis Care Res (Hoboken). 2015 Aug:67(9):1263–1271. doi: 10.1002/acr.22588