Good to know
Right way to hold bag: When holding the SPARROWBAG®, grasp the sand on both sides, or handle it in the middle.
For trainers
Motor muscles
hip (up/extension) m.gluteus maximus, vertebral column (up/extension) m.erector spinae, shoulders (up/flexion, abduction, eccentric rotation) m.deltoideus, m.supraspinatus, m.infraspinatus, m.teres major, m.pectoralis major (claviural part), scapula (up/lifting, upward rotation) m.trapezius upper part, m.levator scapulae, m.serratus anterior, elbow (up/flexion) m.biceps barchii, wrist (up/extension) m.extensor carpi radialis longus, m.extensor carpi radialis brevis, m.extensor carpi ulnaris
Stabilizers
m.erector spinae and m.quadratus lumborum are the basic dynamic stabilizers in keeping the lumbar spine region straight. Furthermore the scapula: m.trapezius lower and middle part, m.levator scapulae, mm.rhomboidei, m.serratus anterior, upper limb: rotator sheath, m.deltoideus, arm muscles, torso: abdominal muscle group, hip: gluteal muscle group, deep eccentric rotators, adductor group