Smooth muscle has no striations, is not under voluntary control, has only one nucleus per cell, is tapered at both ends, and is called involuntary muscle.

Smooth muscle cells

Skeletal muscle is voluntary and responds to conscious stimuli. The cells are striated and multinucleated appearing as long, unbranched cylinders. Each cell is a spindle-shaped fiber and contains a single nucleus. No striations are evident because the actin and myosin filaments do not align in the cytoplasm.

Smooth muscle

The only 100% accurate reading of a muscle fiber type is through a muscle biopsy, but if you’re looking for a practical test that can be done in less than a minute, I highly suggest you use the vertical jump test.

Research shows the pecs are a predominately fast twitch muscle. Therefore, you should train your chest with short, explosive, heavy bouts of exercise. Fewer amounts of sets (2-6) and reps (1-6), in comparison to slow twitch dominant muscles, are necessary to make the pecs grow.

Incorporate more fast-twitch movements by performing reps at a faster rate, or working in exercises like power clean and snatch. Sprints and agility drills – Straight sprints can be quite boring. Try adding changes in motion to your sprint routine, such as there-backs or three-point agility drills.

The gastrocnemius is often called the fast twitch dominant part of the calves, but that’s only compared to the super slow soleus.

The abdomen (Abs) are muscles all the same to the rest of your body. They are derived from both slow twitch muscle fibers, which stimulate better to low weight high reps, and fast twitch muscle fibers, which stimulate better to heavy weight and low reps.

Although the deltoid is often considered to be a fast twitch muscle due to its key role in throwing and punching movements, research that has measured the fiber type of multiple muscles has found it to be relatively slow twitch.

The pectoralis major is a performance muscle and both its heads are predominantly fast twitch in almost everyone, with 60% type II fibers being the average.

Author Michel Gundil found that, “bodybuilders have front delts that are on average five times bigger than sedentary people. Their lateral delts are three times bigger, and their rear delts are only 10 to 15 percent bigger.

The shoulders consist of 3 heads the anterior (front), lateral (side), posterior (rear). Growing big, round delts requires a mixture of heavy weights and high reps. The front delts grow when hit with high weights and usually they are pretty easy to grow.

Best Deltoid Exercises: #1

• Walking Plank. Start in a high plank position.
• Upright Row. Hold a dumbbell in each hand, resting in front of your thigh.
• Rear Delt Fly.
• Lateral Raise.
• Plank with Shoulder Taps.
• Burpee.
• Single-Arm Dumbbell Press.
• Rear Delt Fly.

Push-ups primarily work your pectoral muscles, strengthening your chest. Push ups increase the size and strength of your deltoid muscles, making your shoulders appear wider.

How to lose muscle in your arms and legs

1. lift to failure.
2. increase the number of reps.
3. increase the speed of your lifting.
4. reduce rest time between sets.
5. eat a high calorie, high protein diet.

Types of deltoid injuries Grade 1: a mild muscle sprain that still allows for normal function, but you may experience tightness, a dull ache, or swelling. Grade 2: partial muscle tears that can cause sudden, sharp pain and restrict mobility.

If you have a minor strain, recovery may take one to two weeks. An injury with partial tearing may take four to six weeks. A serious tear can take up to four months to heal.

Deltoid injuries include strains and tears of the muscle. You may feel only slight twinges of pain at the back of your shoulder or may not be able to lift your arm, depending on the grade of your injury. Proper rehabilitation for a deltoid injury can help you retain your range of motion and strength.

For a mild strain, you may be able to return to normal activities within three to six weeks with basic home care. For more severe strains, recovery can take several months. In severe cases, surgical repair and physical therapy may be necessary. With proper treatment, most people recover completely.

Treatment

1. Rest. Avoid activities that cause pain, swelling or discomfort.
2. Ice. Even if you’re seeking medical help, ice the area immediately.
3. Compression. To help stop swelling, compress the area with an elastic bandage until the swelling stops.
4. Elevation.