Sure, achieving a beach-ready physique will require pumped-up "show muscles"—but before you can get there, you'll need to strengthen all the little muscles, too.
As you embark on a three-month training cycle like the Eternal Beach Body workout program, you'll need to mobilize and strengthen your most important joints, particularly your shoulders, hips, and core. Almost every major bodybuilding motion involves one of these, so laying the mobilization groundwork ahead of time will be essential. Feel free to use slightly lighter weights, because you won't need too much force to work your smaller stabilizer muscles.
That's what you'll be doing in this workout, the first of Eternal Beach Body Phase I.
Do each exercise as straight sets; complete all sets of each exercise before moving on to the next.
Make sure you pay attention to the designated rest—45 seconds isn't a lot of time, and you'll be well served by tracking your rest periods on your watch or your phone.