**About the Editors**

**Matteo Cesari**, MD, Ph.D., is Associate Professor of Geriatrics at the University of Milan, and Head of the Geriatric Unit at the IRCCS Istituti Clinici Scientifici Maugeri (Milan, Italy). His research activities are focused on the frailty condition and strategies aimed at preventing the disabling cascade. Dr. Cesari has currently published more than 460 articles in peer-reviewed scientific journals, 21 book chapters, and numerous other publications; more than 200 abstracts of his have been accepted at National and International meetings. Overall, Dr. Cesari's current h-index is 71. He is listed by Clarivate Analytics among the worldwide Highly Cited Researchers (http:// highlycited.com). Dr. Cesari is Editor-in-Chief of *The Journal of Frailty & Aging*, and Senior Associate Editor of the *Journal of the American Medical Directors Association* [JAMDA]. Dr. Cesari also serves as a consultant for the World Health Organization on the themes of aging and integrated care in older people.

**Emanuele Marzetti**, MD, Ph.D., is a board certified Geriatrician, Clinical Assistant Professor in Geriatrics, and the leader of the Orthogeriatric Unit at the Department of Geriatrics, Neurosciences and Orthopedics (Fondazione Policlinico Universitario "Agostino Gemelli" IRCCS, Universit`a Cattolica del Sacro Cuore, Rome, Italy). He received his MD and PhD degrees at the Universit`a Cattolica del Sacro Cuore, and postdoctoral training in biochemistry of aging at the University of Florida (Gainesville, FL, USA). Dr. Marzetti serves as an Associate Editor for *Experimental Gerontology*, *The Journal of Frailty & Aging, JCSM Clinical Reports*, and *Frontiers in Medicine*. His research focuses on the mechanisms responsible for skeletal muscle and cardiovascular aging, with a special interest in mitochondrial pathophysiology, biomarker discovery, and the factors involved in the pathogenesis of frailty and disability in old age.

#### **Preface to "Nutrition for Musculoskeletal Health"**

Malnutrition, mostly in the form of undernutrition, is highly prevalent among older adults, especially in those who are institutionalized. The development of malnutrition during aging is often the consequence of multiple concurring factors, including reduced appetite, sensory impairment (in particular, taste and smell abnormalities), poor oral health, dysphagia, changes in gastrointestinal function and motility, comorbidities, medications, social isolation, inactivity, depression, poverty, etc. Regardless of the underlying cause(s), malnutrition increases the risk of adverse health-related events, among which, musculoskeletal conditions (sarcopenia and osteoporosis) are especially worrisome.

The purpose of this book was to convene experts and opinion leaders in nutrition and the musculoskeletal system to provide a multifaceted and comprehensive view of the impact of malnutrition on musculoskeletal health during and in the setting of specific disease conditions. The book showcases original articles and reviews addressing this subject through pre-clinical, clinical, and translational approaches. Nutritional interventions aimed at improving overall and musculoskeletal health in both humans and experimental models are also presented. Selected contributions illustrate the prospect of using circulating amino acids, either alone or in combination with inflammatory biomolecules and gu<sup>t</sup> microbiota composition, as biomarkers for sarcopenia. The variety of topics and the interdisciplinary content make the book appealing to a large readership, from clinicians interested in implementing nutritional interventions in their daily practice to researchers who may take cues for future studies on the subject.

Lastly, we would like to take the opportunity to thank the contributors, the reviewers, and the MDPI editorial staff, whose scientific excellence, time, and dedication made this book a reality.

> **Matteo Cesari, Emanuele Marzetti** *Editors*

#### **Determinants of Adherence in Time-Restricted Feeding in Older Adults: Lessons from a Pilot Study**

**Stephanie A. Lee 1,\*, Caroline Sypniewski 1, Benjamin A. Bensadon 1, Christian McLaren 1, William T. Donahoo 2, Kimberly T. Sibille 1 and Stephen Anton 1,3,\***


Received: 12 February 2020; Accepted: 17 March 2020; Published: 24 March 2020

**Abstract:** Time-restricted feeding (TRF) is a type of intermittent fasting in which no calories are commonly consumed for approximately 12–18 hours on a daily basis. The health benefits of this eating pattern have been shown in overweight adults, with improvements in cardiometabolic risk factors as well as the preservation of lean mass during weight loss. Although TRF has been well studied in younger and middle-aged adults, few studies have evaluated the effects of TRF in older adults. Thus, the goal of this study was to evaluate older-adult perspectives regarding the real-world advantages, disadvantages, and challenges to adopting a TRF eating pattern among participants aged 65 and over. A four-week single-arm pre- and post-test design was used for this clinical pilot trial TRF intervention study. Participants were instructed to fast for approximately 16 h per day with the daily target range between 14 and 18 h. Participants were provided with the TRF protocol at a baseline visit, along with a pictorial guide that depicted food items and beverages that were allowed and not allowed during fasting windows to reinforce that calorie-containing items were to be avoided. The trial interventionist called each participant weekly to promote adherence, review the protocol, monitor for adverse events, and provide support and guidance for any challenges faced during the intervention. Participants were instructed to complete daily eating time logs by recording the times at which they first consumed calories and when they stopped consuming calories. At the end of the intervention, participants completed an exit interview and a study-specific Diet Satisfaction Survey (Table 1) to assess their satisfaction, feasibility, and overall experience with the study intervention. Of the 10 participants who commenced the study (mean age = 77.1 y; 6 women, 4 men), nine completed the entire protocol. Seven of the ten participants reported easy adjustment to a 16-hour fast and rated the difference from normal eating patterns as minimal. Eight participants reported no decrease in energy during fasting periods, with greater self-reported activity levels in yardwork and light exercise. Adverse events were rare, and included transient headaches, which dissipated with increased water intake, and dizziness in one participant, which subsided with a small snack. The findings of the current trial sugges<sup>t</sup> that TRF is an eating approach that is well tolerated by most older adults. Six participants, however, did not fully understand the requirements of the fasting regimen, despite being provided with specific instructions and a pictorial guide at a baseline visit. This suggests that more instruction and/or participant contact is needed in the early stages of a TRF intervention to promote adherence.

**Keywords:** weight loss; intermittent fasting; fat loss; sarcopenia; body composition
