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.
Stabilizing Muscles. The plank is a full-body exercise, making it valuable in almost any training program. When you perform the plank on your forearms, you activate the trapezius and rhomboids at the upper back. All three deltoid muscles and the rotator cuff at the shoulder work to stabilize your torso.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.