Comparing compound exercises and
trunk flexion exercises, Aspe et al. (2014) explored rectus abdominis muscle activity in a number of exercises including the front and overhead squat performed with 90 % of 3RM, as well as the swiss ball jack knife and straight - leg sit up.
They found increased rectus abdominis muscle activity when performing
trunk flexion exercises with added elastic resistance from a portable device (Perfect Abs).
Assessing the effect of relative load during different
trunk flexion exercises, Sternlicht et al. (2003) compared a number of abdominal exercises (Ab Roller Plus, Torso Track 2, AB - Doer Pro, and the Perfect Abs) to the traditional curl up.
Assessing the effect of stability during both compound and
trunk flexion exercises, Mok et al. (2014) assessed the muscle activity of the abdominals in a number of suspension exercises including the hip abduction plank (feet in straps), press up, inverted row and hamstring curl (feet in straps).
Not exact matches
So many abdominal
exercises involve hip and
trunk flexion — sit - ups, leg raises, crunches — all of them involve drawing the hips and rib cage closer together, potentially causing shortening of the hip flexors.
Imagine an abdominal crunch (or any other core
exercise that involves
trunk flexion) with weak and / or un-engaged pelvic floor and core muscles... You bend at the waist to «crunch» and... Splat.
Unstable surfaces can be utilised with a plethora of dynamic core
exercises and are classically positioned under the
trunk or feet to perform the curl up, sit up or spinal
flexion exercises.
Comparing hamstring strain injury prevention and rehabilitation
exercises, Orishimo & McHugh (2015) found that the supine sliding leg curl (Slider) produced greater gluteus maximus EMG amplitude during the eccentric phase than the standing elastic - band resisted hip extension, the standing
trunk flexion (Glider) or the standing split (Diver).
The researchers this time compared a number of
exercises that utilised the upper - body weight as leverage including static inverted row, L - sit,
trunk extension (static horizontal back extension), static lateral
flexion of the
trunk (static horizontal
flexion).
Patients with PL commonly have compensatory postures (FIGURE 3), including increased cranial weight shift and increased
flexion of the lumbosacral, coxofemoral, and stifle joints.23 To address compensatory patterns,
trunk - and core - strengthening
exercises are also warranted, as are massage and soft tissue mobilization techniques.