Effects of High vs. Low Glycemic Index of Post-Exercise Meals on Sleep and Exercise Performance: A Randomized, Double-Blind, Counterbalanced Polysomnographic Study

Effects of High vs. Low Glycemic Index of Post-Exercise Meals on Sleep and Exercise Performance: A Randomized, Double-Blind, Counterbalanced Polysomnographic Study



The aim of the current study was to investigate the effect of the glycemic index of post-exercise meals on sleep quality and quantity, and assess whether those changes could affect the next day’s exercise performance. Following a baseline/familiarization phase, 10 recreationally trained male volunteers (23.2 ± 1.8 years) underwent two double-blinded, randomized, counterbalanced crossover trials. In both trials, participants performed sprint interval training (SIT) in the evening. Post-exercise, participants consumed a meal with a high (HGI) or low (LGI) glycemic index. Sleep parameters were assessed by a full night polysomnography (PSG). The following morning, exercise performance was evaluated by the countermovement jump (CMJ) test, a visual reaction time (VRT) test and a 5-km cycling time trial (TT). Total sleep time (TST) and sleep efficiency were greater in the HGI trial compared to the LGI trial (p < 0.05), while sleep onset latency was shortened by four-fold (p < 0.05) and VRT decreased by 8.9% (p < 0.05) in the HGI trial compared to the LGI trial. The performance in both 5-km TT and CMJ did not differ between trials. A moderate to strong correlation was found between the difference in TST and the VRT between the two trials (p < 0.05). In conclusion, this is the first study to show that a high glycemic index meal, following a single spring interval training session, can improve both sleep duration and sleep efficiency, while reducing in parallel sleep onset latency. Those improvements in sleep did not affect jumping ability and aerobic endurance performance. In contrast, the visual reaction time performance increased proportionally to sleep improvements.

Authors: Angelos Vlahoyiannis, George Aphamis, Eleni Andreou, George Samoutis , Giorgos K. Sakkas and Christoforos D. Giannaki 

For more information, click here



eHipp Stress Management Workshops for Universal life

eHipp Stress Management Workshops for Universal life

The eHipp team Prof Andreas Anastasiou , Michalis Makris , and Prof George Samoutis delivered to the Universal life personnel interactive workshops on stress management at work . More than 150 employees  attended the seminars in small groups .The feedback was excellent and specific advice has been provided to the company. The Guardian Angel app will complement the eHipp stress management at work interventions.

Guardian Angel Personalized Virtual Coach

Guardian Angel Personalized Virtual Coach

“Guardian Angel” (GA) is an innovative, unique and state-of-the-art mobile health app that focuses on stress management at work, lifestyle intervention, and the improvement of the users’ quality of life.

Prof. George Samoutis

Prof. George Samoutis

Professor George Samoutis is the CEO of eHipp LTD. He is also the Clinical Director of Apostolos Loukas Medical Centre.  He is an experienced  practicing Academic physician MD, PhD, CCT UK, PGCertHBE UK, a Clinical Professor, Deputy Head, Centre for Primary Care and Population Health University of Nicosia Medical School, Academic Lead for Clinical Placements CS&T year and General Practice Curriculum Lead, St George’s, University of London medical programme delivered in Cyprus by the University of Nicosia Medical School. International Associate National Institute for Health and Care Excellence (NICE, UK). CEO of Guardian Angel.

Michalis Makris

Michalis Makris

Michalis Makris is the Business Development Leader of eHipp LTD. He is the Founder and Managing Director of Clover Advice, a boutique consulting firm specializing in Business Development and Strategy.  Prior to Clover Advice, he had worked in the sectors of Banking, Real Estate, Venture Capital and Strategy for organizations in the UK and Cyprus. The geographical markets he covers are Europe, Middle East and the Balkans. He holds an MBA from INSEAD Business School. He also holds two Bachelor Degrees, one in Mathematics and Statistics from Bristol University in the UK and another in Financial Services from UMIST University in the UK.  He is also an Associate Member of the UK Chartered Institute of Bankers (ACIB). Finally he is a graduate of the American Academy of Dramatic Arts in New York and has appeared in international productions on theater, cinema and TV, including the TV series ‘Friends’ and ‘CSI Miami’.

Prof. Andreas Flouris

Prof. Andreas Flouris

Associate Professor Andreas Flouris is the Clinical Leader of eHipp LTD. He is a Senior Researcher in Human Physiology at the University of Thessaly Department of Exercise Science in Greece as well as an Adjunct Professor in Environmental Medicine with the School of Human Kinetics at the University of Ottawa, Canada. He is the Founder and Director of FAME Lab [(F)unctional (A)rchitecture of (M)ammals in their (E)nvironment], a research group of >15 full-time researchers investigating the health and performance effects of environmental factors with a particular focus on the effects of heat. Dr. Flouris is a Coordinator or Partner in several funded projects in the EU and North America (>17M euro in the past 6 years) and he has published widely (>130 research papers) on the effects of different environmental factors on human health and performance. He is a Section Editor for the scientific journal Temperature and an Associate Editor for the scientific journal BMC Pulmonary Medicine.

Prof. Andreas Anastasiou

Prof. Andreas Anastasiou

Professor Andreas Anastasiou is the Psychology/Social/Cognitive Care
Leader of eHipp LTD. He earned his Ph.D. in Counseling Psychology from the University of Pittsburgh, Pennsylvania, USA. He has worked as a psychologist in several settings in the United States including a Veteran’s Affairs hospital, counseling centers, and state agencies. As Associate Professor at Mary Baldwin College in Virginia, USA, he served as chair of the psychology department for four years. He repatriated to Cyprus four years ago and, since then, has been an Associate Professor of Psychology at the University of Nicosia, where he also served as Chair of the Social Sciences Department. He lectures at the Saint George’s of London Medical School at the University of Nicosia and has served as Board member of the Cyprus Psychological Association.

Dr. Zinonas Antoniou

Dr. Zinonas Antoniou

Dr. Zinonas C. Antoniou is ICT leader at eHipp LTD. He received his 5-year Engineering Diploma (Dipl.-Ing.) from the School of Electrical and Computer Engineering, of the National Technical University of Athens. He holds a PhD from Computer Science in the Department of Computer Science of University of Cyprus. He is working as a Teaching Assistant and a Researcher at the Computer Science Department of the University of Cyprus.