I read a Frederic Delavier’s book « Strength Training Anatomy » and there is good stuff.
We spend several hours sitting in a day. It’s relaxing but it can create a problem. This problem is the Kyphosis which is the rounding of the upper back with shoulder enrolement forwards.
We can have this bad position because of the hypotonicity (decreased muscle tone) of muscles bringing together shoulder blades and external rotator muscles of arms or because of the hypertonicity of torso’s muscles (usually for men, excessive training of chest).
As you know, it’s a bad posture and it’s important to rebalance all that. Exercices that do this are exercice that work posterior deltoid (back of shoulder) like one arm rear deltoid fly with cable, low pulley bent-over lateral raises and others.
Note : For deadlift, the rounding of the upper back limits the power of lifting, that why it’s important to straighten your shoulders to use all your potential.
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