The second edition of this book has been thoroughly revised to reflect the latest ACSM guidelines. Several chapters have been expanded to provide more background on various special populations, including clients such as pregnant women, children and various types of heart patients. The case study material has been updated to reflect the ACSM's new screening criteria and latest fitness norms. Moreover, the case studies in the Appendix have been reformatted to allow easier access to the explanations in the answer section. All the great features of the first edition have been retained, such as the reader-friendly format and the use of many practical case studies. The key benefit of this book is that it will help prepare the reader for ACSM certification. It is primarily aimed as a professional reference, especially in preparation for the ACSM Health Fitness Instructor Certification Programme. Some course adoptions as supplemental text will also find this book of use.