legs extended = lower abs bias
legs tucked in = upper abs biasso abs in general
While performing a hanging leg raise one of the intended actions of the primary muscle, the iliopsoas, is to flex the thigh and the trunk during the exercise. Other primary muscles include the rectus femoris, tensor fascia lata, and adductors.
it works your abs
trunk flexion lateral trunk flexion
it works your abs
it works your abs
The agonist muscle used in a side leg raise is the adductor.
The Gastrocnemius (calf muscle) is the primary mover. The Synergist (or assistor) muscle is the Soleus.
The primary muscle used in the seated calf raise is the gastrocnemius; the secondary muscle used is the soleus. Generally-speaking, the more inner, deep-seated muscles are brought into play first in any action - which would be the soleus. Also, in a "seated" raise, I would think the gastrocnemius is not put under any potential strain: it is a very strong muscle as it needs to lift the weight of the whole body; but, then, the soleus is not put under full pressure either in this position. Nevertheless, both are used for such exercises.
The primary muscle used in the seated calf raise is the gastrocnemius; the secondary muscle used is the soleus. Generally-speaking, the more inner, deep-seated muscles are brought into play first in any action - which would be the soleus. Also, in a "seated" raise, I would think the gastrocnemius is not put under any potential strain: it is a very strong muscle as it needs to lift the weight of the whole body; but, then, the soleus is not put under full pressure either in this position. Nevertheless, both are used for such exercises.
Yes
Crunches
the heel, in particular the calcaneus. the joint utilised being the tibiotalar joint.