Sleep, Melatonin, Musculoskeletal Health and COVID-19…..What’s the Link?

New Studies Reveal Impact of Sleep and Melatonin on Physical Health and Disease Prevention in Adults and Adolescents

We all know how sleep deprivation can negatively affect health – impacting everything from our cognitive ability and immune response to heart function and disease prevention.

Now additional research underscores the important role that sleep plays in musculoskeletal health and the surprising link between melatonin, a key component in inducing sleep, and COVID-19.

The studies, which recognized that the pandemic has fueled anxiety related insomnia weakening the immune system vital in combating a host of diseases, including COVID-19, revealed that not only has melatonin (a hormone released primarily by the pineal gland at night) shown to improve restorative sleep but also immune response – potentially providing added protection against COVID-19.

According to a Cleveland Clinic study, researchers found that “melatonin reduced the likelihood of study participants getting COVID-19 by 28%.”  Among black participants, a population disproportionately affected by the disease, “infection likelihood was reduced by 52%.”1

The study further indicated that aside from potentially preventative benefits, melatonin may also help aid in the treatment of COVID-19 “due to its antioxidant and anti-inflammatory effects.”

Another study found that taking melatonin to improve sleep in the two weeks prior to a COVID-19 vaccination could help ensure that the vaccine is taken amid optimal sleep conditions, when the immune system is at its best.  And using melatonin for at least two to four weeks following receipt of the vaccine may enhance the body’s immune response to the vaccine and possibly increase length of time a person has immunity.2

If this information isn’t compelling enough, as COVID begins to increasingly affect younger population groups, data from the Centers for Disease Control and Prevention (CDC) show that insufficient sleep – common among high school students – is associated with an “increased risk for unintentional injury from drowsy driving crashes, sports injuries and occupational injuries.”3

The data showed that students reporting less than seven hours of sleep per night were more likely to report several injury-related risk behaviors than those sleeping nine hours or more.

The lack of sleep in both adult and adolescent population groups can be attributed to a number of factors, including anxiety, nutritional deficiencies impacting melatonin production, and over exposure to “blue light” affecting the body’s natural circadian rhythm (24-hour cycles that regulate sleep patterns and essential function based on sunrise and sunset).

Synthesized from tryptophan, an essential dietary amino acid, melatonin production can be impacted by nutritional factors such as the intake of vegetables, caffeine and some vitamins and minerals – though with less intensity than light, which is “the most dominant synchronizer of melatonin production.”4

According to the Sleep Foundation, blue light is a portion of the visible light spectrum that can affect alertness, hormone production and sleep cycles. It is emitted by LED and fluorescent lights, as well as many electronic devices.  Blue light is the largest disrupter of natural circadian rhythm and melatonin production.5

It is important to monitor behavior and discuss changes in sleep and activity patterns with your physician to determine if inadequate melatonin levels and disrupted sleep cycles are compromising restorative sleep and protective immune system function. Melatonin supplements, dietary changes and behavior modifications may be recommended.


  1. Zhou Y, Hou Y, Shen J, Mehra R, et al. A network medicine approach to investigation and population-based validation of disease manifestations and drug repurposing for COVID-19. PLOS Biology. 2020. journal.pbio.3000970.
  2. Cardinali DP, Brown GM, and Pandi-Perumal SR. An urgent proposal for the immediate use of melatonin as an adjuvant to anti SARS-COV-2 vaccination. Melatonin Res. .
  3. Wheaton AG, Olsen EO, Miller GF, and Croft JB. Sleep duration and injury-related risk behaviors among high school students – United States, 2007-2013. Centers for Disease Control and Prevention (CDC). 2016;65(13):337-341.
  4. Peuhkuri K, Sihvola N, and Korpela R. Dietary factors and fluctuating levels of melatonin. Food Nutr Res. 2012;56:10.3402/fnr.v56i0.17252.
  5. Newsom R. How blue light affects sleep. 2021 June 24. Sleep Foundation.


This information is provided for educational purposes only and does not replace a discussion with your healthcare provider.

Dr. Korsh Jafarnia is one of Houston’s leading board certified, fellowship trained hand and upper extremity specialists.  A member of Houston Methodist Orthopedics & Sports Medicine, Dr. Jafarnia also serves as an assistant professor in the Department of Orthopedic Surgery at Weill Cornell-affiliated Houston Methodist Hospital. Call 888.621.HAND (4263) for an appointment, or go to to learn more.

Pitcher’s Elbow


Today’s youth sports are more demanding than ever.  Seasons are longer and the practice and game schedule is intense.  Though with proper training and the ability to understand what pain may be signaling, a career ending injury can be avoided.

One of the more common overuse sports injuries we see affects the elbow and is known as Pitcher’s Elbow.

Throwing a baseball, particularly repeatedly as a pitcher does, puts a tremendous amount of stress on the inside of the elbow.  This stress is concentrated on a ligament known as the ulnar collateral ligament (UCL).

Lateral Collateral Ligament / Ulnar Collateral Ligament

When there is pain on the inside of the elbow it may mean that the ligament has either been stretched or has micro-tears.  The goal is to avoid throwing to the point of such pain, as it may indicate that the damage is already done!

There are many factors that can lead to the injury of a young player’s elbow ligament.  The main problem is throwing too much.  Often times this player is young, talented and needed in much of the game in order for the team to win.  The player then gets “overplayed,” until the elbow pain prevents further throwing.  The team must then find another pitcher and the cycle repeats.

Below are some suggestions that will hopefully help young pitchers – enabling them to mature and develop their full potential before an injury cuts their season short:

1. Pitch Count

The definitive pitch count guideline generally adopted comes from the 1996 American Sports Medicine Institute (ASMI) study.  This guideline includes maximum pitches per day, and days of rest between pitching.  Below are websites that include more information on this.

2. All Season Baseball

As our youth become more competitive, they begin to play year round.  This includes spring…..and now also summer and fall.  The elbow never gets a chance to rest and re-strengthen.  Ideally, the young athlete would pursue a different sport during the off-season – engaging different muscles, ligaments and tendons.  If baseball is the only sport, the pitcher must limit the amount of pitching during the off-season and work on some of the other influencing factors listed below.

 3. Pitching Mechanics

The mechanics of pitching are often left to the weekend warrior coach.  It may be worthwhile to find a professional pitching coach who can not only see the subtle corrections that need to be made, but also find a way to help the player make these adjustments as they throw at ever increasing velocity.  Consider that the player is developing as he gets older.  This means that the lessons from last year may no longer apply.  Players are not only getting taller, but developing more muscle.  This will impact their pitching mechanics.  A player should be re-evaluated every year or two.

 4. The Shoulder

Pitching is a rotation sport!  The windup starts in the body and gets transmitted to the hand via the shoulder and elbow.  If the shoulder is weak, the elbow must compensate.  This leads to injury.  It is important to strengthen the shoulder, chest and back in order to support this movement.  Specifically, it is important to strengthen the shoulder muscles that rotate the shoulder called the rotator cuff.  It is also important to strengthen the muscles that control the shoulder blade (scapula).  Young players have open growth plates in their bones, and injury to these growth plates are avoided by keeping the weight low.  The goal is not to build bulk but rather to build strength and stamina.  Weight training is best done in the off-season.   Smaller muscles like the rotator cuff can be exercised two or three times per week.  More than three times a week will weaken and not strengthen these muscles.  Finally, it is important to stretch the shoulder joint, especially the posterior capsule.  This is done by bringing the arm across the body and feeling the stretch on the back of the shoulder.

5. Fatigue

There is a difference between strength and fatigue.  As the game progresses, the muscles become fatigued.  The player, in their effort to maintain speed, start to use other muscles and change their throwing mechanics.  This then leads to increased strain on the elbow and ultimately to injury.  This may be avoided by strengthening the upper muscles in the off-season and by watching the pitch count during the season.

6. Addressing an already painful elbow

Pain in the elbow could indicate that the elbow is injured.  The first step is to stop playing baseball and seek the assessment of an orthopedic specialist.

–  Once pain is resolved and the tenderness is completely gone, initiate a strengthening program focusing on muscles of the chest, back and shoulders

– After the strengthening program is well on its way, the player should seek an evaluation by a professional pitching coach.

-Gradually the player will increase pitching distance and speed – with particular focus on proper mechanics

– After completing these steps, players can return to the regular season.

Typically, once a player has elbow pain they generally require about six months to complete the steps above.  Since the pain often occurs at the start or middle of a pitching season, this usually means that they will lose out on the remainder of that season.  Though, this is preferable to permanently damaging the arm and eliminating any chance of playing another season.

Helpful Websites:   (pitch count regulation)