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.
Easier Version. If you are not quite able to perform a side plank on the elbow with good form, you can modify the exercise to strengthen many of the same muscles. Instead of extending your legs, bend your knees so your forearm and the side of one knee support your body weight.econdary Muscles. The side plank also works several other muscles that provide additional stability as you hold the position. These muscles include the gluteus maximus, the quadriceps on the front of your thighs and the hamstrings on the back of your thighs.