I'm Zhao Xiaodao and I'm an ophthalmologist.
We know that intraocular pressure is an important factor influencing the development of myopia, and the axis of the eye ultimately grows under the action of intraocular pressure. Clinically, it was found that there was a significant association between intraocular pressure and the development of myopia, especially high myopia. For children with high underlying intraocular pressure, intraocular pressure control is also a non-negligible part of myopia prevention and control.
Have you heard that exercise can also lower intraocular pressure? The following table is the effect of different exercises on intraocular pressure found in current research, which can be used as a reference for parents when designing exercises for their children:
| Type of exercise | effect | The amount of impact | duration |
| jogging | lower | 5.64mmhg | < 30 minutes |
| Ride a bike | lower | 2.70mmhg | 10 minutes |
| Swimming (eye socket goggles) | elevated | 2.32mmhg | 60 minutes |
| Grip exercises | elevated | 25% | / |
| Squats | elevated | / | 10 seconds |
| Elected | elevated | / | 10 seconds |
| Raise the bar Ling | elevated | / | 10 seconds |
| Weight-bearing calf raises | elevated | / | 10 seconds |
| Yoga (lower head) | elevated | 2 times | / |
Recently, the International Review of Ophthalmology published a review "The relationship between exercise and intraocular pressure, ocular blood perfusion and optic nerve protection" (authors Lin Jingjing, Liang Yuanbo, Nie Li) - a large number of previous studies have confirmed that high-intensity aerobic exercise can effectively reduce intraocular pressure.
In 2009, a large cohort study of more than 27,000 male runners from running clubs across the United States showed a strong dose-dependent relationship between the incidence of glaucoma and weekly running habits, i.e., lower rates of glaucoma in those who ran farther, faster, and more than 10 kilometers a day.
Recently, data from South Korea's National Health and Nutrition Survey showed that among 10,243 men over the age of 40 who exercised moderate to vigorously, the incidence of glaucoma was significantly lower than that of non-exercisers.
A 5-year cohort study of intraocular pressure changes in 1871 participants in Japan also showed that increased exercise frequency and increased exercise duration were significantly associated with a decrease in intraocular pressure.
01
What exercises can lower intraocular pressure?
Motion can be divided into isotonic motion and isometric motion.
Isotonic movement
Isotonic exercise means that during exercise, muscle fibers are shortened when the muscle contracts, but the muscle tone does not change significantly.
Such as: running, cycling, swimming, rowing, aerobics, skipping rope, skiing, etc
Previous studies have confirmed that different types of isotonic exercises have transient mild to moderate intraocular pressure lowering effects.
Young male volunteers who performed high-intensity exercise on a treadmill stopped when their heart rate reached 85% of their expected heart rate and achieved a decrease in intraocular pressure of 5.64 mmHg after 1 minute, although the positive effect lasted no more than 30 minutes. - "Clin Exp Ophthalmol" by Kozobolis, et al
A 30-minute cycling exercise immediately resulted in an IOP drop of 2.70 mmHg, but the IOP lowering effect lasted only 10 minutes. - "Optom Vis Sci Najmanova", Najmanova, etc
After 6 minutes of the ladder test, the intraocular pressure decreased significantly compared with the previous one, and the intraocular pressure lowering time was maintained for 60 minutes. - Eye (Lond), Okuno et al
It is important to note that swimming is inherently beneficial for IOP, but the use of goggles and the prone position may increase IOP.
Intraocular pressure increased by 2.32 mmHg immediately after goggles were put on and remained until the goggles were removed (60 minutes). The vacuum cavity formed by the goggles, the external water pressure, and the pressure of the goggles on the periorbital tissues may be responsible for the increase in IOP, and the smaller the facial area of the goggles, the greater the increase in IOP. —"Yonsei Med J" by Ma et al
Isometric movements
Isometric movement means that during exercise, the tension of the muscles increases when the muscles contract, while the muscle fibers do not shorten.
Such as: weightlifting, grip strength, plank, static crunch, handstand, bridge, squat, barbell, clean and jerk hold, pull-up hold, etc
In contrast to isotonic exercise, isometric exercise has a transient effect on intraocular pressure. Experiments in humans and animals have found that the increase in intraocular pressure during isometric exercise is proportional to the increase in blood pressure and is partly influenced by the measurement of partial pressure of carbon dioxide.
Continuous real-time intraocular pressure (IOP) detection was performed on 9 healthy young volunteers during 2-minute grip exercises, and it was found that intraocular pressure gradually increased with the increase of systemic blood pressure, with an amplitude of about 25%. —Invest Ophthalmol Vis Sci, by Bakke et al
Intraocular pressure (IOP) increased rapidly during 2 minutes of different types of isometric exercises (squats, presses, forearm bends, calf raises) and returned to baseline 10 seconds after exercise. —Optom Vis Sc, by Vera et al
(Note: Studies by other investigators have shown that intraocular pressure did not change significantly in healthy subjects after 6 minutes of squatting with a significant increase in blood pressure.) )
Some researchers believe that the increase in intraocular pressure caused by some isometric exercises that require weight-bearing (such as squats, barbell lifts, etc.) may be related to the Valsalva maneuver. This may be related to the increase in central venous pressure during the Valsalva maneuver and subsequent obstruction of venous return, resulting in an increase in superficial scleral venous pressure and thus intraocular pressure. - Eur J Sport Sci, Vera et al
The Valsalva maneuver is an action named after an Italian scientist who means that we hold our breath after taking a deep inhale, not letting the gas come out of our mouths or nasal passages, and must hold our breath. In this breath-holding situation, do as much as you can exhale. The main purpose of the Valsalva maneuver is to reduce venous return by increasing the pressure in the body's chest cavity.
Some isometric exercises (e.g., yoga, etc.) may involve changes in body position, and intraocular pressure can also increase during exercise, especially yoga movements with the head facing down, which can even cause intraocular pressure to rise to twice the baseline level. - PLoS One, by Nelson et al
02
Why exercise lowers blood pressure
The mechanism by which exercise alters intraocular pressure is not well understood, and isotonic and isometric movements may involve different mechanisms.
In most past reports, it has been suggested that isotonic exercise may stimulate many transmitters and cause more systemic metabolic changes than isometric exercise, such as increased plasma colloidal osmolality, decreased norepinephrine concentration, increased blood lactate, and decreased blood pH, thereby contributing to the reduction of intraocular pressure. At the same time, this effect seems to fade quickly over time.
Does exercise increase intraocular pressure worsen glaucoma?
Although there is evidence of an association between isometric exercise and increased intraocular pressure, it is difficult to conclude that isometric exercise does worsen glaucoma and accelerate vision loss, as exercise-induced intraocular pressure usually returns to normal after a few minutes or even immediately after exercise.
03
Does exercise intensity and time have an effect on intraocular pressure?
Intraocular pressure decreases
Previous studies have shown that the degree of intraocular pressure drop is positively correlated with isotonic exercise intensity within a certain range, but not with exercise time.
As early as 1995, researchers conducted a controlled study on the intraocular pressure lowering effect of different exercise intensities, and divided them into three groups: light (walking), moderate (jogging) and high intensity (running), and found that the intraocular pressure of the three groups of healthy subjects decreased by 2.43, 3.85 and 4.0 mmHg respectively after exercise, and the higher the intensity of exercise at different exercise time points, the more obvious the effect of reducing intraocular pressure.
Similar results were shown in cycling studies of different intensities: after 10 minutes of cycling at 170 beats per minute, IOP was significantly reduced by 2.3 mmHg, but extending the exercise time to 20 or 30 minutes did not enhance this effect, suggesting that prolonged exercise did not enhance the degree of IOP reduction.
Increased intraocular pressure
Currently, research on isometric exercise is limited by a shorter duration. The researchers observed that squats led to immediate and cumulative increases in intraocular pressure and were positively correlated with the applied load. Among them, during the 1-minute squat exercise, the average intraocular pressure increase was 24%, 37%, and 41% in the low, moderate, and high-load groups, respectively, while after 1 minute of exercise, the intraocular pressure in the low, moderate, and high-load groups increased by 36%, 52%, and 59%, respectively. Other studies have also found that intraocular pressure gradually increases as the number of exercise repetitions accumulates.
Well, that's all for today's sharing, I hope to bring you some inspiration and provide some reference when choosing sports for children.
I am Zhao Xiaodao
I am an ophthalmologist