Daily backpacker budget: $20 ~ $35. Bolivia is the ultimate cheapie of South America. Things may be very basic here as itâs a dirt poor country but your dollars sure go a long way. It is the cheapest country for accommodation and the cheapest for food and drink as well.
The plank strengthens the abdominals, back, and shoulders. Muscles involved in the front plank include: 1  Primary muscles: erector spinae, rectus abdominis (abs), and transverse abdominus.he plank strengthens the abdominals, back, and shoulders. Muscles involved in the front plank include: 1  Primary muscles: erector spinae, rectus abdominis (abs), and transverse abdominus.
Primary Muscles. The primary muscles the plank works are the erector spinae, the rectus abdomimus and the transverse abdominus. The erector spinae is a large muscle that runs up the length of the back. It surrounds your spine and allows you to straighten your back and rotate side to side.he plank is one of the simplest and most effective abdominal exercises. In its most basic form, you brace yourself at the top of a pushup while contracting your core muscles. You can do multiple variations of the plank to create more challenge and target different parts of the core.