Afterword – closing the loop: Observations and conclusions Chapter uri icon


  • © selection and editorial matter, J. Timothy Lightfoot, Monica J. Hubal and Stephen M. Roth; individual chapters, the contributors. All Rights Reserved. This conclusion presents some closing thoughts on the concepts covered in the preceding chapters of this book. The book provides an exciting look into one of the more dynamic research areas in exercise and sport sciences. It provides experimental proof that some exercise phenotypes may be the result of multiple different genetic architectures — a confirmation of the “multiple independent evolutionary solution�? hypothesis in genetics. The primary challenge facing investigators considering the systems genetics of physical activity is the need for more hypothesis-driven, causative studies. The book focuses on the anthropological evolution of the endurance phenotype and underlying mitochondrial physiology and genetics. It explores heritability estimates of endurance-related traits, splitting the literature into animal- and human-based evidence, both providing high estimates of heritability of baseline endurance, with lower estimates of heritability for response to training, indicating that contributions of environmental factors to variance in training responses are substantial.

author list (cited authors)

  • Lightfoot, J. T., Hubal, M. J., & Roth, S. M.

complete list of authors

  • Lightfoot, JT||Hubal, MJ||Roth, SM

Book Title

  • Routledge Handbook of Sport and Exercise Systems Genetics

publication date

  • January 2019