Fitness for You - Lower Body Exercises

© Copyright Peter Crawford 2012
LOWER BODY EXERCISES


The lower body is often neglected.
Lower body exercises are energy intensive and difficult, but they are essential because of their anabolic effects (see below).
With the development of a new generation of exercise machines, lower body exercises can now be undertake in complete safety, and such machines enable the lower body to be exercised with unparalleled efficiency.

Quadriceps (quadriceps femoris) (front of thigh)

Leg press
Leg extension







DO NOT perform 'Squats' in order to exercise the quads.
Squats put an unnacceptable strain on the verterbrae of the back.
Once you have a compressed vertebrae you have it for life.
Modern machines such as the stack leg press machine and the plate leg press machine are more effecient at exercising the quads and, in addition, are much safer.




The quadriceps femoris (Latin for "four-headed muscle of the femur"), also called simply the quadriceps, quadriceps extensor, quads, (see diagram above) is a large muscle group that includes the four prevailing muscles on the front of the thigh.
It is the great extensor muscle of the knee, forming a large fleshy mass which covers the front and sides of the femur.
It is subdivided into four separate portions or 'heads', which have received distinctive names:
Rectus femoris occupies the middle of the thigh, covering most of the other three quadriceps muscles. It originates on the ilium. It is named from its straight course.
The other three lie deep to rectus femoris and originate from the body of the femur, which they cover from the trochanters to the condyles:
Vastus lateralis is on the lateral side of the femur (i.e. on the outer side of the thigh).
Vastus medialis is on the medial side of the femur (i.e. on the inner part thigh).
Vastus intermedius lies between vastus lateralis and vastus medialis on the front of the femur (i.e. on the top or front of the thigh), but deep to the rectus femoris. Typically, it cannot be seen without dissection of the rectus femoris.
All four parts of the quadriceps muscle ultimately insert into the tibial tuberosity of the tibia. This is via the patella, where the quadriceps tendon becomes the patellar ligament, which then attaches to the tibia.
The best exercise for the quadriceps is the leg press (see Life Fitness stack leg press machine and plate leg press machine - left).
This exercise also develops the gluteus maximus, and is an essential exercise as it has an anabolic effect * on the whole body.

*Anabolic processes tend toward "building up" organs and tissues.
These processes produce growth and differentiation of cells and increase in body size, a process that involves synthesis of complex molecules. Examples of anabolic processes include the growth and mineralization of bone and increases in muscle mass.
Endocrinologists have traditionally classified hormones as anabolic or catabolic, depending on which part of metabolism they stimulate.
The classic anabolic hormones are the anabolic steroids, which stimulate protein synthesis and muscle growth.
The balance between anabolism and catabolism is also regulated by circadian rhythms, with processes such as glucose metabolism fluctuating to match an animal's normal periods of activity throughout the day.



The isolation movement (i.e. targets solely the quadriceps) is the leg extension exercise (see Life Fitness stack leg extension machine - right).






The Glutes and Quadriceps can be developed by using the combined glute and quadriceps machine (see Life Fitness  glute and quadriceps machine  - right)







Leg Bicep (biceps femoris) (rear of thigh)

Leg curl


The biceps femoris is a muscle of the posterior (the back) thigh.
As its name implies, it has two parts, one of which (the long head) forms part of the hamstrings muscle group.
It has two heads of origin;
one, the long head, arises from the lower and inner impression on the back part of the tuberosity of the ischium, by a tendon common to it and the semitendinosus, and from the lower part of the sacrotuberous ligament;
the other, the short head, arises from the lateral lip of the linea aspera, between the adductor magnus and vastus lateralis, extending up almost as high as the insertion of the gluteus maximus; from the lateral prolongation of the linea aspera to within 5 cm. of the lateral condyle; and from the lateral intermuscular septum.

The fibers of the long head form a fusiform belly, which passes obliquely downward and lateralward across the sciatic nerve to end in an aponeurosis which covers the posterior surface of the muscle, and receives the fibers of the short head; this aponeurosis becomes gradually contracted into a tendon, which is inserted into the lateral side of the head of the fibula, and by a small slip into the lateral condyle of the tibia.

At its insertion the tendon divides into two portions, which embrace the fibular collateral ligament of the knee-joint.

From the posterior border of the tendon a thin expansion is given off to the fascia of the leg. The tendon of insertion of this muscle forms the lateral hamstring; the common fibular (peroneal) nerve descends along its medial border.
Both heads of the biceps femoris perform knee flexion.
Since the long head originates in the pelvis it is also involved in hip extension.
The long head of the biceps femoris is a weaker knee flexor when the hip is extended (because of active insufficiency). For the same reason the long head is a weaker hip extender when the knee is flexed.
When the knee is semi-flexed, the biceps femoris in consequence of its oblique direction rotates the leg slightly outward.

The biceps femoris is exercised by using the leg curl machine (see Life Fitness stack leg curl machine - right).


Calf Muscle (soleus)

Calf Raises

The soleus is a powerful muscle in the back part of the lower leg (the calf).
It runs from just below the knee to the heel, and is involved in standing and walking.
It is closely connected to the gastrocnemius muscle and some anatomists consider them to be a single muscle, the triceps surae.
The soleus is located in the superficial posterior compartment of the leg.
The short head of the biceps femoris develops in the flexor compartment of the thigh and is thus innervated by common peroneal branch of the sciatic nerve (L5, S2), while the long head is innervated by the tibial branch of the sciatic nerve (L5, S2).

The soleus is exercised by using the calf-raise machine (see Life Fitness plate calf raise - right).

Adductor Muscles of the Hip

In human anatomy, the adductor muscles of the hip is a group of muscles of the thigh.
The adductors originate on the pubis and ischium bones. and insert on the medial, posterior surface of the femur.
The Adductor Muscles of the Hip are exercised by using the hip machines (see Life Fitness plate hip machines - left)














© Copyright Peter Crawford 2012


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