• Your account starts with a full list: three delt heads, chest regions, traps, lats and more.
• Tag an exercise with Select muscles when you create or edit it.
• The routine editor counts how often each muscle is hit per cycle and lists the ones that aren't trained at all.
• Train → Muscles shows which exercises use each muscle, by group. New muscle adds your own.
• Searching for a muscle? Type its name or its group: chest, shoulders, or everyday words like back, legs, arms or core show every muscle in it. This works on Muscles, in Select muscles, on Exercises (the exercises that work them) and in Search.

Muscle groups

Every muscle belongs to one fixed group: chest, shoulders (delts), biceps, triceps, forearms, abs and core, hip flexors and groin (the front of the hip: hip flexors, adductors, or a muscle of your own such as the pelvic floor for Kegels), lats, traps and upper back, lower back, glutes, quads, hamstrings, calves, neck, or cardio (heart and lungs). The groups can't be changed; you choose which group a muscle of your own belongs to when you add or edit it (Strenla's own muscles already have theirs, and a name it knows picks its group for you). Muscles without a group are listed at the end of Muscles; open one to give it a group.

The body diagram

A front and a back figure light up the groups worked, brighter for the ones worked more. You'll find it:

• on an exercise's page (Muscles it works);
• on Train, Muscles today at the top: tap it to see each muscle, how many of today's exercises hit it, and the body;
• in Focus mode, with Muscles (the exercise on screen);
• in the routine editor (Muscles hit per cycle, as you change it), and on the Plan setup and Workout planner review;
• on a muscle's own page, with its group.