Targeting your iliopsoas, not your rectus abdominis, the lying straight leg raise is an isolation pull exercise that activates all hip flexor muscles.
The diamond push-up on knees is a brilliant beginner exercise for triceps development. Synergists include the pectoralis major and anterior deltoid.
The twisting hyperextension is a compound bodyweight exercise that targets your erector spinae, hamstrings, and obliques. Your glutes act as synergists.
Use the weighted inverted row to build your back muscles and develop upper-body strength. Instead of a weight plate, you can use a weighted vest or chain.
Build upper-body strength and mass, engage your core, and improve your functional strength using the weighted push-up, a compound push exercise.
Target your hamstrings and erector spinae (spinal erectors) with the one-leg hyperextension. You gluteus maximus and adductor magnus act as synergists.
Great for core development, the captain's chair leg and hip raise is a compound hip-and-waist-flexion exercise that targets your rectus abdominis.
An advanced core exercise, use the standing ab wheel rollout only after you have mastered the walkout, front plank, and wheel rollout on your knees.
An advanced bodyweight exercise, the bodyweight fly (aka rollout fly) can be an isolation or compound exercise depending on whether you extend your elbows.
Great for beginners, the bodyweight sumo squat is useful for learning the very basics of squat form (keeping your torso upright, knees out, and head up).
Targeting your pecs, anterior deltoids, triceps, and elbow flexors, the isometric wiper is a compound bodyweight exercise, good for burning out your chest.
The stability ball push-up doesn't build mass; however, it does recruit more stabilizers and provide a better functional and core workout than the push-up.