Mechanisms of Ageing and Development

Frailty syndrome increases the risk for disability and mortality, and is a major health concern amidst the geriatric shift in the population. High intensity interval training (HIIT), which couples bursts of vigorous activity interspersed with active recovery intervals, shows promise for the treatment of frailty. Here we compare and contrast five Fried physical phenotype and one deficit accumulation based mouse frailty assessment tools for identifying the impacts of HIIT on frailty and predicting functional capacity, underlying pathology, and survival in aged female mice. Our data reveals a 10-minute HIIT regimen administered 3-days-a-week for 8-weeks increased treadmill endurance, gait speed and maintained grip strength. One frailty tool identified a benefit of HIIT for frailty, but many were trending suggesting HIIT was beneficial for physical performance in these mice, but the 8-week timeframe may not have been insufficient to induce frailty benefits. All frailty tools distinguished or trended towards distinguishing between surviving or non-surviving mice, whereas half correlated with functional capacity measured by nest building ability, and none correlated with underlying pathology. Overall, there was correlation between Fried based frailty assessment tools, but little agreement with the deficit-accumulation tool. This study supports the ongoing development of mouse assessment tools for frailty research.

Cell division times for immortalised Hs68-TERT, Mid-passage Hs68 and Late-passage Hs68 human fibroblasts.