A Fitness-Fatigue Model of Performance in Peripheral Artery Disease: Predicted and Measured Effects of a Pain-Free Exercise Program

Abstract

Banister impulse-response (IR) model estimates the performance in response to the training impulses (TRIMPs). In 100 patients with peripheral artery disease (PAD), we tested by an IR model the predictability of the effects of a 6-month structured home-based exercise program. The daily TRIMPs obtained from prescribed walking speed, relative intensity and time of exercise determined the fitness-fatigue components of performance. The estimated performance values, calculated from the baseline 6-min and pain-free walking distance (6MWD and PFWD, respectively) were compared with values measured at visits through regression models. Interval pain-free walking at controlled speed prescribed during circa-monthly hospital visits (5 ± 1) was safely performed at home with good adherence (92% of scheduled sessions, 144 ± 25 km walked in 50 ± 8 training hours). The mean TRIMP rose throughout the program from 276 to 601 a.u. The measured 6MWD and PFWD values increased (+33 m and +121 m, respectively) showing a good fit with those estimated by the IR model (6MWD: R2 0.81; PFWD: R2 0.68) and very good correspondence (correlation coefficients: 0.91 to 0.95), without sex differences. The decay of performance without training was estimated at 18 ± 3 weeks. In PAD, an IR model predicted the walking performance following a pain-free exercise program. IR models may contribute to design and verify personalized training programs.

Lower All-Cause Mortality Risk in Females and Males with Peripheral Artery Disease following Pain-Free Home-Based Exercise: A 7-Year Observational Study

“…Considering home-based programs, no significantly different response to the exercise intervention according to sex was reported [74]. At discharge from the present graded program, no different functional outcomes were observed between sexes, nor a different response to training in a fitness fatigue model of performance developed in PAD [41,42].…”

“…Unfortunately, for rehabilitative outcomes, sex differences are also reported, with participation in exercise programs in PAD, as in various chronic diseases, being limited by barriers in terms of referral, enrollment, and completion and outcomes, particularly among women [36][37][38]. Conversely, a structured pain-free exercise program for PAD patients prescribed at a hospital and performed at home designed to reduce most barriers to exercise [39,40] proved to obtain adherence and functional outcomes without gender differences [41,42].…”