Safety of the Squat Exercise
The squat is typically a barbell exercise where the individual starts in a standing position with the barbell on the back, and bends the knees to squat down until the thighs are parallel with the floor. It has been the subject of some controversy in exercise prescription, primarily related to the belief that it causes knee or low back pain or injury. However, when examining the safety of the squat, it is appropriate to review the history, science, and practical application of this activity.
Any resistance exercise improperly performed may result in injury. Such injury may occur due to excessive volume of training, excessive resistance, or use of improper form in performing the exercise. Thus, exercise technique is paramount.
 

Historical Perspective
Scientific evidence that squatting movements could be detrimental to the knee came from work reported in the 1960s. The squat exercise, properly done, reportedly stretched the knee ligaments in both medial/lateral and posterior/anterior directions. Based on this work, some military services in the United States ceased using squatting movements (specifically jump squats without resistance) in their training programs.
Possible flaws regarding this research include choice of subjects and investigators’ bias. Subjects in one of the studies were parachute jumpers. Medial/lateral knee ligament injuries are common in this group, because

1) the legs are often caught in parachute lines as it opens, and

2) parachutists place excessive force on the knee joint when landing.

Recent Scientific Evidence-the Knee

Since work from the 1960s, several research studies have expanded our knowledge and understanding in this area. These include studies made on athletes, animals and individuals who have been through injury rehabilitation. One study used an instrument to measure anterior/posterior displacement of the tibia relative to the femur. Subjects performed varying depths of squats over an eight-week period. Additional data were collected on groups of weightlifters, power lifters, and age-matched controls. Over the eight-week period, there was no increased instability created relative to depth of the squat. Thus, squats do not negatively affect knee stability. Using the same instrument, another group of researchers determined that acute bouts of exercise using a variety of activities (including squats) decreased stability of the knee joint, possibly due to muscle fatigue or elevated body temperature. Therefore, knee instability is not necessarily due to one specific exercise movement such as the squat. However, many exercises can cause acute instability due to other factors.

Various forms of exercise have been shown to increase ligament strength.

In animal studies, endurance exercise has been shown to increase the strength of the ligament-bone attachment, as well as increasing the diameter and collagen content of ligaments. When bone-ligament preparations are tested at high speeds, they fail at a higher maximum load. In athletes rehabilitating injured knees, closed-chain exercises such as the squat are currently used because in the squat, the hamstrings co-contract with other leg muscles to increase the stability of the knee, thus putting less stress on the anterior cruciate ligament.
There are certainly times in the healing of injuries where the squat, and other exercises that stress the knee, should be avoided. However, once soft tissues have healed, exercises should be chosen that are the most effective at improving strength to protect the knee joint from further injury.
 

The Stress of Squats on the Back

Another area of concern for safety in the squat exercise is the low back. If the lift is not properly performed, the forces at the low back maybe intense enough to cause injury.

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The most common errors that may lead to back problems include 1) lifting excessive weight and 2) leaning over too far so the weight is lifted by the back and not the legs and hips. Squatting with resistance placed on the upper back across the shoulders does increase the compressive forces on the spine. Maintaining an erect posture helps to evenly distribute the forces on the spine, and to decrease the chance of injury. Forces at the lumbar spine on half-squats with a loaded barbell were determined to be six to ten times the body weight. To reduce both spinal compressive forces and shear forces, the athlete should have the necessary flexibility of the knee, hip and spine to maintain an upright posture during the squat.
Abdominal strength is also important to protect the spine. During a heavy lift, lifters hold their breath during the effort portion of the lift. This increases intra-abdominal pressure and helps stabilize the spine. Wearing a weight belt may also help the athlete exert intra-abdominal pressure. While there is some controversy about the use of weight belts, they probably should be used during heavy squat lifts.
Stress fractures of the vertebra (spondylolysis) and forward slippage of one vertebra over another (spondylolisthesis) do occur in athletes. Because athletes are generally active in a variety of ways, including resistance training, it is difficult to determine whether resistance training is a possible cause of these conditions. Maintaining strong torso musculature is essential in protecting the spine during the squatting movement. The squat program should be modified for athletes with back problems.
Back pain is a common complaint associated by some with the squat exercise. Sprains and strains may occur with a variety of athletic activities and are more likely to occur with sudden movements involving spinal extension and rotation. Properly performed, the squat exercise does not fit into this category. In one study, weightlifters had a relatively low incidence of back pain (eight of 80 lifters). This study indicates that spinal flexibility, lifting with a straight back, and strong paravertebral muscles protect the lifter from back pain. In former lifters, the incidence of low back pain was less than in the general population.
 

Proper Use of Squats in a Training Program
As mentioned earlier, any exercise can be performed improperly. Athletes enter training programs with different strength levels and past injuries. All of these factors must be considered when developing a strength program. Proper technique taught by qualified personnel is important to the safety of the squat exercise. The depth of the squat is generally recommended to the point where the tops of the thighs are parallel with the floor. With proper form and progression, certain athletes may be able to descend lower. The value of deep squats for improving athletic performance continues to be a debated topic. In general, if the athlete is required to perform from a deep squat position, such as in weightlifting, that athlete should gradually progress to the deep squat position.
Training while overly fatigued or training to failure with squats may place the athlete at risk of losing control of the squat and therefore losing control of the weight, allowing a twisting motion at the knee, increasing the potential for meniscal injuries to the knee. Time for adequate recovery should be allowed (both within the exercise session and from one exercise session to the next), and the resistance and repetitions should be adjusted appropriately.

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Proper Form
1. Use an approximate shoulder-width foot stance.
2. Descend in a controlled manner.
3. Ascend at a variety of speeds, including fast but controlled speeds.
4. Exhale after the major effort on the ascent.
5. Avoid bouncing or twisting in the bottom position.
6. Maintain a normal lordotic posture with an erect spine.
7. Descend to the point where the tops of the thighs are parallel to the floor.
8. Keep feet flat on the floor.
9. In general, be sure knees do not go beyond the toes.
10. Keep progression of both resistance and depth of the squat gradual, and do not exceed the body’s capacity to adapt to the imposed demands. Warning symptoms for progressing too fast include back pain, knee pain, and other symptoms of overtraining.
11. Consider fatigue to be a risk factor in squatting.
12. Maintain proper form, or stop performing the exercise.

Summary
In summary, the squat exercise is important to many athletes because of its functionality and similarity to athletic movements. If appropriate guidelines are followed, the squat is a safe exercise for individuals without a previous history of injuries. The squat is a large-muscle-mass exercise and has excellent potential for adding lean muscle mass with properly prescribed exercise.
The squat trains a high number of muscles, focusing on the lower body and back. Individuals with prior injury or special considerations (e.g. pregnant women) need to consult their physician before starting any exercise program.

Written for the American College of Sports Medicine by Jeff Chandler, Ed.D., C.S.C.S., FACSM, Jim McMillan, Ed.D., C.S.C.S., W. Ben Kibler, M.D., FACSM, and David Richards, M.D.
Current Comments are official statements by the American College of
Sports Medicine concerning topics of interest to the public at large.
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13 THINGS MENTALLY TOUGH PEOPLE DON'T DO.   Amy Morin

 

1. They don't waste time feeling sorry for themselves.

"Feeling sorry for your self is self-destructive," she writes. "Indulging in self-pity hinders living a full life."

It wastes time, creates negative emotions, and hurts your relationships.

The key is to "affirm the good in the world, and you will begin to appreciate what you have," Morin writes. The goal is to swap self-pity with gratitude.

2. They don't give away their power.

People give away their power when they lack physical and emotional boundaries, Morin writes. You need to stand up for yourself and draw the line when necessary. 

If other people are in control of your actions, they define your success and self-worth. It's important that you keep track of your goals and work towards them. 

Morin uses Oprah Winfrey as an example of someone with a strong grip on their power. Winfrey grew up dealing with poverty and sexual abuse, but "she chose to define who she was going to be in life by not giving away her power," she says.

3. They don't shy away from change.

There are five stages of change, Morin writes: pre-contemplation, contemplation, preparation, action, and maintenance.

Following through with each of the five steps is crucial. Making changes can be frightening, but shying away from them prevents growth. "The longer you wait, the harder it gets," she says, and "other people will outgrow you."

4. They don't focus on things they can't control.

"It feels so safe to have everything under control, but thinking we have the power to always pull the strings can become problematic," Morin writes. 

Trying to be in control of everything is likely a response to anxiety. "Rather than focusing on managing your anxiety, you try controlling your environment," she says. 

Shifting your focus off the things you can't control can create increased happiness, less stress, better relationships, new opportunities, and more success, Morin writes. 

5. They don't worry about pleasing everyone.

Oftentimes, we judge ourselves by considering what other people think of us, which is the opposite of mental toughness.

Morin lists four facts about constantly trying to be a people-pleaser: It's a waste of time; people-pleasers are easily manipulated; it's OK for others to feel angry or disappointed; and you can't please everyone.

Dropping your people-pleasing mindset will make you stronger and more self-confident.

6. They don't fear taking calculated risks.

People are often afraid to take risks, whether it's financial, physical, emotional, social, or business-related, Morin writes. But it comes down to knowledge.

"A lack of knowledge about how to calculate risk leads to increased fear," Morin writes.

To better analyze a risk, ask yourself the following questions:

What are the potential costs? •What are the potential benefits?
How will this help me achieve my goal?
What are the alternatives?
How good would it be if the best-case scenario came true?
What is the worst thing that could happen, and how could I reduce the risk it will occur?

7. They don't dwell on the past.

The past is in the past. There's no way to change what happened, and "dwelling can be self-destructive, preventing you from enjoying the present and planning for the future," Morin writes. It doesn't solve anything and can lead to depression, she writes. 

There can be a benefit to thinking about the past, though. Reflecting on the lessons learned, considering the facts rather than the emotions, and looking at a situation from a new perspective can be helpful, she says.

8. They don't make the same mistakes over and over.

Reflecting can ensure you don't repeat your mistakes. It's important to study what went wrong, what you could have done better, and how to do it differently next time, Morin writes.

Mentally strong people accept responsibility for the mistake and create a thoughtful, written plan to avoid making the same mistake in the future.

9. They don't resent other people's success.

Resentment is like anger that remains hidden and bottled up, Morin writes. 

Focusing on another person's success will not pave the way to your own, since it distracts you from your path, Morin writes. Even if you become successful, you may never be content if you're always focusing on others. You may also overlook your talents and abandon your values and relationships, she says. 

10. They don't give up after the first failure.

Success isn't immediate, and failure is almost always an obstacle you will have to overcome. "Take, for example, Theodor Giesel — also known as Dr. Seuss — whose first book was rejected by more than 20 publishers," Morin writes. And now Dr. Seuss is a household name.

Thinking that failure is unacceptable or that it means you aren't good enough does not reflect mental strength. In fact, "bouncing back after failure will make you stronger," Morin writes.

11. They don't fear alone time.

"Creating time to be alone with your thoughts can be a powerful experience, instrumental in helping you reach your goals," Morin writes. Becoming mentally strong "requires you to take time out from the busyness of daily life to focus on growth."

Here are some of the benefits of solitude Morin lists in her book:

-Solitude at the office can increase productivity.
-Alone time may increase your empathy.
-Spending time alone sparks creativity.
-Solitary skills are good for mental health.
-Solitude offers restoration.

12. They don't feel the world owes them anything.

It's easy to get angry at the world for your failures or lack of success, but the truth is no one is entitled to anything. It must be earned.

"Life isn't meant to be fair," Morin writes. If some people experience more happiness or success than others, "that's life — but it doesn't mean you're owed anything if you were dealt a bad hand."

The key is to focus on your efforts, accept criticism, acknowledge your flaws, and don't keep score, Morin writes. Comparing yourself to others will only set you up for disappointment if you don't receive what you think you're owed, she says.

13. They don't expect immediate results.

"A willingness to develop realistic expectations and an understanding that success doesn't happen overnight is necessary if you want to reach your full potential," Morin writes. 

Mentally weak people are often impatient. They overestimate their abilities and underestimate how long change takes, she says, so they expect immediate results.

It's important to "keep your eyes on the prize" and relentlessly work towards your long-term goals. There will be failures along the way, but if you measure your progress and look at the big picture, success will become attainable