Double-Network Hydrogel Stretching (IMAGE) Hokkaido University Caption A double-network hydrogel (i). After stretching (ii), brittle sections break, allowing a generation of mechanoradicals, indicated by color change (iii). Credit Gong J. P. et al., Mechanoresponsive self-growing hydrogels inspired by muscle training, <em>Science</em>, February 1, 2019 Usage Restrictions This image is copyrighted and can be used for reporting this press release if properly credited. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.