Exercise grows bigger fish

Image of gilthead sea bream By Roberto Pillon - http://www.fishbase.us/photos/UploadedBy.php?autoctr=13070&win=uploaded, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=20825139

A new study published in the American Journal of Physiology - Regulatory, Integrative and Comparative Physiology explored the effects of exercise on growth and hormone regulation in gilthead sea bream (Sparus aurata). The main hormones that regulate growth are, perhaps not surprisingly, growth hormone and insulin-like growth factor. Researchers discovered young gilthead seam bream that underwent sustained moderate exercise for 5 weeks gained more weight than fish that were not exercised. The exercised fish also had higher levels of the hormone insulin-like growth factor in their blood along with higher levels of a hormone associated with increased protein synthesis in their muscles (i.e. the production of new muscle cells). This is interesting as plasma levels of growth hormone actually decreased with exercise.

Aside from understanding the effects of exercise on the growth and development of fish, this research has important implications for developing or improving the sustainability of aquaculture.

Source:

EJ Vélez, S Azizi, A Millán-Cubillo, J Fernández-Borràs, J Blasco, SJ Chan, JA Calduch-Giner, J Pérez-Sánchez, I Navarro, E Capilla, J Gutiérrez. Effects of sustained exercise on GH-IGFs axis in gilthead sea bream (Sparus aurata). American Journal of Physiology - Regulatory, Integrative and Comparative Physiology. 310(4): R313-R322, 2016. DOI: 10.1152/ajpregu.00230.2015