Effects of a dual task vs. multicomponent exercise program in long-term nursing home residents

Subjects in both the Control and the Intervention group will undertake a multicomponent exercise program that has previously been described regarding the volume, intensity, type and duration of the exercises by the present research group (Rodriguez-Larrad et al., 2017). Moreover, the feasibility, safety and beneficial effects on long-term nursing home residents have also been published (Arrieta et al., 2018). Subjects will participate in a multicomponent exercise program designed to improve strength and balance conducted by an experienced physical trainer. The programme´s technical content is based on a specific literature review including authors’ expertise and field experience. It has specific objectives and a standardised framework (combination and sequence of exercises), but the goals are individualized based on each participants’ level of physical fitness. Goals will be adapted in response to illness, injury or physical symptoms. The intervention has been designed to meet the exercise and physical activity guidelines for older adults established by the American College of Sport Medicine (ACSM) and American Heart Association. The intervention will consist of 45 minute group supervised sessions conducted twice a week where the exercises will be directed to improve strength and balance. An interval of at least 48 hours between training sessions will be respected. All sessions will begin with a brief warm-up of 5 minutes (range-of motion exercises for the neck, wrists, shoulders, hip, knees and ankles). Strength training (25 minutes) will comprise upper and lower body exercises performed with external weights, which will be tailored to the individual´s functional capacity through Brzycki equation for the estimation of 1-RM (repetition maximum) at baseline and at the end of every month, to ensure an appropriate training stimulus. In all strength tests subjects will be encouraged verbally to perform each exercise as forcefully as possible. In the first month exercises will be performed with light loads (40-50% 1-RM) to ensure an appropriate adaption to resistance exercise and thereafter loads will be increased to 60-70% 1-RM for additional benefits if well tolerated. Balance training (10 minutes) will include exercises in progressing difficulty starting by decreasing arm support (with 2 arms at first, with one hand, and finally none if possible) along with decreasing base of support (both feet together, semi-tandem and tandem positions) and increasing complexity of movements as to challenge participants´ balance as they progress. Exercises will be varied through the period: weight transfer from one leg to another, walking with small obstacles, propioceptive exercises and stepping practice. Sessions will finish with 5 minutes of cooling down by stretching, breathing and relaxing exercises. The intervention will be performed in groups of 5-8 participants, in the facilities of their nursing-home Training attendance will be recorded by the physical trainer every session. Additionally, subjects of the Intervention group will perform cognitive tasks simultaneously to the physical exercises, this attention-demanding physical performance carrying out two tasks (physical + cognitive) at the same time are known as Dual Task (DT). In the DT training, during the multicomponent exercises, concurrent individually tailored cognitive tasks relying predominantly on executive function will be applied to the physical training. Challenge of DT-s will be increased by augmenting complexity of motor tasks (progressing from sitting to standing and from static to dynamic exercises, reducing base of support, etc) and/or cognitive tasks (number of stimulus, complexity of word categories, etc). The first week of the intervention will mainly serve to familiarize participants with the strength and balance exercises and adequate the level of difficulty of each cognitive function to every participant in the group. Thereafter on the second week, strength tests will be performed to individualize strength training and ensure training intensity. Throughout the following weeks dual tasking will be applied mostly in strength exercises to train for divided attention allocation and progressively move to balance exercises to optimize training adaptations and mimic everyday situations that require double tasking and increasing instability. Cognitive training will be conducted based on six main cognitive essential functions for everyday life activities: 1) One of the most important functions to train is attention, which will be applied in form of: a) divided attention tasks (DAT) (both with a secondary physical or a cognitive task) where participants will have to divide their attention to ensure task achievement; b) sustained attention tasks (SAT), in which attention will have to be maintained throughout a certain time period (1-2 minutes); c) shifting, where participants will have to shift their attention just like in everyday situations. 2) In addition, semantic fluency will consist of naming words according to different categories with increasing difficulty such as naming animals, professions or even dog breeds. 3 and 4) Other executive functions including calculus or inhibitory control will also be trained, the latter consisting of overriding the natural response after certain stimulus. 5 and 6) Finally, due to the fact that movement coordination as well as movement learning and sequencing are inherent to any exercise-based program, these will be present in both multicomponent and dual task groups. Bibliography: Rodriguez-Larrad A, Arrieta H, Rezola C, Kortajarena M, Yanguas JJ, Iturburu M, Susana MG, Irazusta J. Effectiveness of a multicomponent exercise program in the attenuation of frailty in long-term nursing home residents: study protocol for a randomized clinical controlled trial. BMC Geriatr. 2017;17(1):60. doi: 10.1186/s12877-017-0453-0. Arrieta H, Rezola-Pardo C, Zarrazquin I, Echeverria I, Yanguas JJ, Iturburu M, Gil SM, Rodriguez-Larrad A, Irazusta J. A multicomponent exercise program improves physical function in long-term nursing home residents: A randomized controlled trial. Exp Gerontol. 2018;103:94-100. doi: 10.1016/j.exger.2018.01.008.