The Influence of Sports Activities on the Intraocular ...

In fulfillment of the

Master’s degree

(M.Sc.) Vision Science and Business (Optometry)

at the faculty of Aalen University, Germany

in cooperation with

New England College of Optometry, Boston, MA, USA,

and

Pacific University College of Optometry, Forest Grove, OR, USA

The Influence of Sports Activities on the Intraocular Pressure – A Review

by

Katharina Kalb

MASTER’S THESIS

Advisors:

Prof. Dr. Anna Nagl, Aalen University

M. Sc. Yvonne Gier, Hecht Contactlinsen GmbH

August 2021

Katharina Kalb Master’s Thesis

“There is nothing, Sir, too little for so little a creature as man. It is by studying little things that we attain the

great art of having as little misery and as much happiness as possible.”

- Samuel Johnson-


Abstract iii

Abstract Purpose: The aim is to be able to advise patients on the choice of sports and exercises regarding the effects on the intraocular pressure.

Methods: The search engines Google Scholar and PubMed were used to search for suitable studies. The studies were summarized, and the most important data were collected in one table for each study. The effect on the IOP was extracted or, if not given in the article, calculated by the difference of means of the IOP after or during exercise, and the baseline IOP before, whenever these values were available.

Findings: A total of 47 studies out of the years 1990 to 2020 that investigated the influence on the IOP of the most popular sports actively practiced in Germany were reviewed and summarized: twelve for running, sixteen for fitness/ weight training, one for swimming/diving, twelve for cycling, four for hiking, and two for yoga. Conclusions: Throughout all studies and sports it was seen that physical fitness stabilized the IOP. Higher intensity of exercise led to higher fluctuations of the IOP. Moderate endurance training keeps the IOP fluctuations low and may lead to a lower baseline IOP if practiced on a regular base. Fitness and weight training lead to fluctuations of the IOP in a pronounced manner when performed at moderate and high intensity. Therefore, only a moderate training can be recommended if there is need to keep the IOP stable. Isometric exercise is not recommended as it provokes a rise of the IOP even when performed with light loads. The Valsalva Maneuver should always be avoided as it leads to additional fluctuations of the IOP. Also, the IOP behaved more stable during resistance training when higher fitness was present.

Keywords: IOP; physical fitness; exercise; sport; IOP fluctuations; physical effort;


Table of contents iv

Table of contents

Abstract ........................................................................................................................................................ III

Table of contents .......................................................................................................................................... IV

List of Figures ................................................................................................................................................ VI

List of Tables ................................................................................................................................................ VII

List of Abbreviations ...................................................................................................................................... X

1 Introduction ........................................................................................................................................... 1

1.1 Motivation for this Thesis ..................................................................................................................... 1

1.2 Previous Reviews .................................................................................................................................. 1

1.3 The Intraocular Pressure ...................................................................................................................... 1

1.3.1 Normal Range of the Intraocular Pressure ....................................................................................... 2

1.3.2 Variations of the Intraocular Pressure ............................................................................................. 2

1.3.3 Glaucoma ......................................................................................................................................... 3

1.3.4 Ocular Hypertension ........................................................................................................................ 4

2 Material and Methods ............................................................................................................................ 4

2.1 Sports in Germany ................................................................................................................................ 4

2.2 Review of Studies ................................................................................................................................. 4

3 Findings .................................................................................................................................................. 5

3.1 Running ................................................................................................................................................ 5

3.2 Fitness/ Weight Training .................................................................................................................... 18

3.3 Swimming/ Diving ............................................................................................................................... 36

3.4 Cycling ................................................................................................................................................ 37

3.5 Hiking (Walking/ Marching) ................................................................................................................ 51

3.6 Yoga .................................................................................................................................................... 56

4 Discussion and Conclusion .................................................................................................................... 58

4.1 Discussion of Findings and Conclusion for Running ........................................................................... 58

4.1.1 The Influence of Running Exercises on the IOP in Glaucoma Patients ........................................... 58

4.1.2 The Influence of Running Exercise on the IOP in Sedentarians ...................................................... 59

4.1.3 The Influence of Running Exercise on the IOP in Trained Subjects ................................................ 60

4.1.4 Comparison of the Effect of One Running Exercise on the IOP of Different Groups of Subjects. .. 60

4.1.5 Comparison of the Effect of High-Intensive Interval Training (HIIT or HIT) with Moderate Exercise in Running on the IOP .................................................................................................................................. 61

4.1.6 The Long-term Effect of Running Exercise on the IOP ................................................................... 62

4.1.7 Flaws of the Findings ...................................................................................................................... 62

4.1.8 Conclusion ...................................................................................................................................... 62


Table of contents v

4.2 Discussion of Findings and Conclusion for Fitness/ Weight training .................................................. 62

4.2.1 The Effect of Exercise Intensity on the IOP and the Role of Physical Fitness ................................. 62

4.2.2 Comparison of the Effect of Isometric and Isokinetic Exercise on the IOP .................................... 64

4.2.3 The Influence of Fitness/ Weight training of the Upper and Lower Limb on the IOP .................... 64

4.2.4 The Influence of Fitness/ Weight training with and without Valsalva Maneuver on the IOP ........ 65


4.2.6 Conclusion ...................................................................................................................................... 66

4.3 Discussion of Findings and Conclusion for Swimming/ Diving ........................................................... 66

4.3.1 Conclusion ...................................................................................................................................... 66

4.4 Discussion of Findings and Conclusion for Cycling ............................................................................. 67

4.4.1 The Effect of Cycling Exercise Intensity and Duration on the IOP .................................................. 67

4.4.2 The Influence of Physical Fitness on the IOP Behavior after Cycling Exercise ............................... 67

4.4.3 The Influence of Cycling Exercise on the IOP in Elderly Subjects ................................................... 68

4.4.4 The Influence of the usage of Glaucoma Medication on the IOP .................................................. 68


4.4.6 Conclusion ...................................................................................................................................... 70

4.5 Discussion of Findings and Conclusion for Walking/ Hiking ............................................................... 70

4.5.1 Conclusion ...................................................................................................................................... 71

4.6 Discussion of Findings and Conclusion for Yoga ................................................................................. 71

4.6.1 Conclusion ...................................................................................................................................... 71

5 Final Words .......................................................................................................................................... 72

Appendix ..................................................................................................................................................... vii

References .................................................................................................................................................. viii

Declaration ................................................................................................................................................. xiv


List of Figures vi

List of Figures Figure 1: Most Popular Sports in Germany in 2018 based on the Results of a Statista Survey from 2018 on the

Most Actively Practiced Sports in Germany on 1047 People Older than 18 Years; translated from german by the author (36). .............................................................................................................................................. 4

Figure 2: The Effect of Running Exercises on the IOP in Glaucoma Patients ....................................................... 59

Figure 3: The Effect of Running Exercises on the IOP in Sedentarians ................................................................ 59

Figure 4: The Effect of Running Exercise on the IOP in Young Adult Sedentarians ............................................. 60

Figure 5: The Effect of Running Exercise on the IOP in Trained Subjects ............................................................ 60

Figure 6: The Effect of Running Fast until Exhaustion on the IOP in different Groups of Subjects ..................... 61

Figure 7: The Effect of Running Exercise on the IOP in Trained and Untrained Subjects. ................................... 61

Figure 8: The Effect of Exercise Intensity of Ballistic Bench Press on the IOP in High Fit, Low Fit and Active Subjects ..................................................................................................................................................................... 63

Figure 9: The Effect of Exercise Intensity of Jump Squats on the IOP in High Fit, Low Fit and Active Subjects ... 63

Figure 10: The Effect of Fitness Exercise of the Upper and Lower Limb on the IOP ............................................ 65

Figure 11: The Effect of Fitness/ Weight training with Valsalva Maneuver and with Normal Breathing on the IOP. ..................................................................................................................................................................... 65

Figure 12: The Effect of Cycling Exercise Intensity and Duration on the IOP ....................................................... 67

Figure 13: The Effect of Cycling Exercise on the IOP in Trained and Untrained Subjects .................................... 68

Figure 14: The Effect of Cycling Exercise on the IOP combined with Glaucoma Medications ............................. 69

Figure 15: The Combined Effect of Glaucoma Medication and Cycling Exercise on the IOP ............................... 70

Figure 16: The Effect of Common Yoga Postures on the IOP ............................................................................... 71


List of Tables vii

List of Tables Table 1: Normal intraocular pressure in [mmHg] based on Hollows FC, Graham PA. Intra-ocular pressure,

glaucoma, and glaucoma suspects in a defined population. (9) .................................................................... 2

Table 2: Number of Studies reviewed sorted by Type of Sport .............................................................................. 5

Table 3: Results for Running out of ”Effects of mild, moderate and severe exercise on intraocular pressure of sedentary subjects ” (37) ............................................................................................................................... 6

Table 4: Results for Running out of ”Effects of Mild, Moderate and Severe exercise on intraocular Pressure in Glaucoma Patients” (38) ................................................................................................................................ 7

Table 5: Results for Running out of ”Effects of Exercise in Intraocular Pressure in Physically Fit Subjects” (39) ... 9

Table 6: Results for Running out of ”Correlating intraocular pressure, blood pressure, and heart rate changes after jogging” (42) ...................................................................................................................................... 10

Table 7: Results for Running out of ”Effect of Acute Submaximal Exercise on Intraocular Pressure in Athletes and Sedentary Subjects” (43) .............................................................................................................................. 11

Table 8: Results for Running out of ”Long-Term Effect of Mild Exercise in Intraocular Pressure in Athletes and Sedentary Subjects” (44) .............................................................................................................................. 12

Table 9: Results for Running out of ”Comparison of the Effect of Acute and Regular Exercise on Intraocular Pressure in Turkish Athlete and Sedentarians” (40) ..................................................................................... 13

Table 10: Results for Running out of ”Effects of High-Intensity Interval vs. Continuous Moderate Exercise on Intraocular Pressure” (45) ............................................................................................................................ 14

Table 11: Results for Running out of ”Influence of Exercise on Intraocular Pressure, Schlemm´s Canal and the Trabecular Meshwork” (46) ......................................................................................................................... 14

Table 12: Results for Running out of ”Acute intraocular pressure response to high-intensity interval-training protocols in men and women” (47) .............................................................................................................. 15

Table 13: Results for Running out of ”Effect of maximal treadmill test on intraocular pressure and ocular perfusion pressure: The mediating role of fitness level” (48) ....................................................................................... 16

Table 14: Results for Running out of “Aerobic exercise reduces intraocular pressure and expands Schlemm´s canal diameter in healthy and primary open-angle glaucoma eyes” (49) ............................................................ 17

Table 15: Results for Fitness/ Weight training out of “Isocapnia Blocks Exercise-Induced Reductions in Ocular Tension” (50) ................................................................................................................................................ 18

Table 16: Results for Fitness/ Weight training out of “Moderate exertion lasting only seconds reduces intraocular pressure” (51) .............................................................................................................................................. 19

Table 17: Results for Fitness/ Weight training out of ”The Comparison of Intraocular Pressure Reduction after Isometric and Isokinetic Exercise in Normal Individuals” (52) ...................................................................... 19

Table 18: Results for Fitness/ Weight training out of ”The acute effects of resistance exercise on intraocular pressure” (53) .............................................................................................................................................. 20

Table 19: Results for Fitness/ Weight training out of ”Intraocular Pressure Variation During Weightlifting” (54) ..................................................................................................................................................................... 21


List of Tables viii

Table 20: Results for Fitness/ Weight training out of ”Comparison of the influence of aerobic and resistance exercise of the upper and lower limb on intraocular pressure” (41) ............................................................ 22

Table 21: Results for Fitness/ Weight training out of ”The acute effect of strength exercise at different intensities on intraocular pressure” (55) ....................................................................................................................... 23

Table 22: Results for Fitness/ Weight training out of ”Fitness Level Modulates Intraocular Pressure Responses to Strength Exercises” (56) ............................................................................................................................... 25

Table 23: Results for Fitness/ Weight training out of “Effect of the level of effort during resistance training on intraocular pressure” (57) ............................................................................................................................ 28

Table 24: Results for Fitness/ Weight training out of “Investigating the Immediate and Cumulative Effects of Isometric Squat Exercise for Different Weight Loads on Intraocular Pressure: A Pilot Study” (58) ............. 29

Table 25: Results for Fitness/ Weight training out of “Acute intraocular pressure changes during isometric exercise and recovery: The influence of exercise type and intensity, and participant´s sex” (59) ................ 30

Table 26: Results for Fitness/ Weight training out of “Impact of resistance training sets performed until muscular failure with different loads on intraocular pressure and ocular perfusion pressure”(60) ............................ 31

Table 27: Results for Fitness/ Weight training out of “Intraocular Pressure Responses to Four Different Isometric Exercises in Men and Women” (61) ............................................................................................................. 32

Table 28: Results for Fitness/ Weight training out of “Intraocular pressure increases during dynamic resistance training exercise according to the exercise phase in healthy young adults” (62) ........................................ 33

Table 29: Results for Fitness/ Weight training out of “Influence of the breathing pattern during resistance training on intraocular pressure” (63) ....................................................................................................................... 34

Table 30: Results for Fitness/ Weight training out of “The intraocular pressure response to lower-body and upper-body isometric exercise is affected by the breathing pattern” (64) ............................................................. 35

Table 31: Results for Swimming out of “Effect of repeated endurance exercise on intraocular pressure in healthy subjects: a prospective pilot study based on a 500-km swim relay” (65) .................................................... 36

Table 32: Results for Cycling out of ”Effect of bicycle ergometer test on intraocular pressure in elderly athletes and controls” (67) ........................................................................................................................................ 37

Table 33: Results for Cycling out of ”Correlates of Acute Exercise-Induced Ocular Hypotension” (68) ............... 38

Table 34: Results for Cycling out of ”Effects of Exercise in Intraocular Pressure in Physically Fit Subjects” (39) . 40

Table 35: Results for Cycling out of ”Magnitude of Decrease in Intraocular Pressure Depends upon Intensity of Exercise” (69) ............................................................................................................................................... 41

Table 36: Results for Cycling out of ”Effect of Exercise on Intraocular Pressure and Pulsatile Ocular Blood Flow in a Young Norma Population” (70) ................................................................................................................. 42

Table 37: Results for Cycling out of ”Comparison of the Effect of Acute and Regular Exercise on Intraocular Pressure in Turkish Athlete and Sedentarians (40)” ..................................................................................... 43

Table 38: Results for Cycling out of “Aerobic exercise and intraocular pressure in normotensive and glaucoma patients” (71) ............................................................................................................................................... 44

Table 39: Results for Cycling out of ”Comparison of the influence of aerobic and resistance exercise of the upper and lower limb on intraocular pressure” (41) .............................................................................................. 46


List of Tables ix

Table 40: Results for Cycling out of ”Intraocular Pressure Responses to Maximal Cycling Sprints Against Different Resistances: The Influence of Fitness Level”(72) .......................................................................................... 47

Table 41: Results for Cycling out of “Effects of a Short-term Cycle Ergometer Sprint Training Against Heavy and Light Resistance on Intraocular Pressure Responses” (73) .......................................................................... 48

Table 42: Results for Cycling out of “Baseline Intraocular Pressure Is Associated with Subjective Sensitivity to Physical Exertion in Young Males”(74) ........................................................................................................ 50

Table 43: Results for Cycling out of “Effects of caffeine consumption on intraocular pressure during low-intensity endurance exercise: A placebo- controlled, double-blind, balanced crossover study” (75) ......................... 50

Table 44: Results for hiking out of ”The Effect of Continuous Strenuous Exercise on Intraocular Pressure” (76) 51

Table 45: Results for Walking out of ”Effects of mild, moderate and severe exercise on intraocular pressure of sedentary subjects” (37) .............................................................................................................................. 52

Table 46: Results for Walking out of ”Effects of Mild, Moderate and Severe exercise on intraocular Pressure in Glaucoma Patients” (38) .............................................................................................................................. 54

Table 47: Results for Walking out of “Walking for a Short Distance at a Brisk Pace Reduces Intraocular Pressure by a Clinically Significant Amount” (77) ....................................................................................................... 55

Table 48: Results for Yoga out of ”Intraocular Pressure Rise in Subjects with and without Glaucoma during Four Common Yoga Positions” ............................................................................................................................. 56

Table 49: Results for Yoga out of ”Intraocular Pressure Changes and Ocular Biometry during Sirsasana (Headstand Posture) in Yoga Practitioners” (79) ......................................................................................... 57


List of Abbreviations x

List of Abbreviations AH Aqueous humor

AE Aerobic exercise

C/D Cup-To-Disc

CO2 Carbon dioxide

h Hour

HRmax Heart rate maximum

IOP Intraocular pressure

mmHg Millimeters of mercury

ms Milliseconds

OD Oculus dexter/ right eye

OS Oculus sinister/ left eye

OU Oculus utriusque/ both eyes

POAG Primary open angle glaucoma

Rep Repetition

RM Repetition maximum

SC Schlemm`s canal

SD Standard deviation

VF Visual field

VO2max Maximal oxygen consumption

Wmax Individual maximum power


Introduction 1

1 Introduction

1.1 Motivation for this Thesis In 2019, I attended the annual alumni meeting in Bendediktbeuern organized by the Aalen Friends of Optometry e.V.. One of the topics on the program was "Lifestyle Modification for Prevention & Management of Glaucoma", presented by Ryan Bulson. This presentation included interesting studies on the behavior of intraocular pressure (IOP) with exercise.

I began following the current research, primarily because of my interest in IOP behavior during the exercises I practiced myself. The more I read, the more I saw how many studies there already were.

This work is a review which includes studies from 1990 to 2020. It leads to conclusions regarding training while needing or wanting to optimize IOP behavior, whether due to risk for developing glaucoma, already existing glaucoma, or other ocular health problems that require stable or low IOP. The aim is to be able to advise patients on the choice of sports and exercises regarding the effects on the intraocular pressure.

This work does not claim to be exhaustive.

1.2 Previous Reviews Previously, other authors have discussed the influence of exercise on intraocular pressure in reviews (1–4). Four papers were found in which the influence of sport on the IOP was at least part of the work.

Risner et al. found that after exercise the IOP is acutely decreased. This effect was of shorter duration after dynamic exercise compared to isometric exercise. Training led to lowered baseline IOP, and physically fit subjects showed a less pronounced effect on the IOP after exercise. In healthy subjects autoregulation of the vascular system resulted in stable ocular blood flow although ocular perfusion pressure was elevated (1).

Gale et al. found that the IOP decreased after dynamic exercise and returned to baseline within one hour. They found no evidence that repeated physical activity reduces the IOP at rest. They highlighted the advantages of exercising for ocular health. The risk for central retinal vein occlusion and neovascular age-related macular degeneration is reduced by regular physical activity. Another benefit is, that systemic hypertension and diabetes, which both have consequences for the health of the eye, improve with regular exercise. (2).

Wylegala saw that dynamic exercises reduces the IOP only for a short time, but in general it was found that aerobic exercises decreased the IOP while for anaerobic, isometric, and resistance training the outcomes were controversial (4).

Zhu et al. found that dynamic exercise is effective in lowering the IOP, exception was found in patients with pigment dispersion syndrome and pigment dispersion glaucoma. Regarding isometric exercise they found a transient increase during this way of exercising (3).

1.3 The Intraocular Pressure The intraocular pressure is maintained by aqueous humor (AH). It is formed in the ciliary body by the nonpigmented cells being an ultrafiltrate of plasma. The functions of the aqueous humor include providing nutrition to and removing metabolic waste from the lens, trabecular meshwork, and cornea. In addition it is part of the optical system of the eye by having the characteristics of being clear and colorless. (5)

AH leaves the eye via two pathways:

i. The conventional pathway (from trabecular meshwork into Schlemm´s canal and aqueous veins) (6)


Introduction 3

minimum) of the IOP to be 5mmHg in normal eyes, 5.8mmHG in eyes with open angle Glaucoma, 6.8 mmHg in eyes with ocular hypertension, and 5.9mmHg in eyes with chronic angle closure glaucoma (12).

1.3.2.2 Short-term IOP fluctuations

Short-term IOP fluctuations appear during the circadian IOP variations. Measurement of IOP in a lying position showed higher values compared to a seated position (13). The lateral decubitus position also leads to an increase of the IOP (the dependent eye more) (14). Neck flexion or extension leads to an increase of the IOP (15). Holding breath (Valsalva maneuver) has also an increasing effect on IOP (16). Drinking a large amount of water within a short time leads to an increase of intraocular pressure (17). Does an individual experience psychological stress it´s IOP may also react with rising (16). In addition accommodation showed to lower IOP (18).

IOP variations during exercise and the long-term effect of exercise on the IOP are the main part of this work and will be discussed later.

1.3.2.3 Variations of the Intraocular Pressure – a risk?

IOP variation has been suggested as an independent risk factor for glaucoma. After 64 patients with glaucoma performed self-tonometry at home five times per day for five days, Asrani et al. found out that large fluctuations of the IOP during the day were a significant risk factor for progression of the diseases (19).

On the other hand, Bengtsson et al. investigated on the fluctuations of the IOP and glaucoma progression in the early manifest glaucoma trial. The main variables of interest were the mean IOP at all applicable visits, which were scheduled every 3 months, and IOP fluctuation, defined as the standard deviation of IOP at these visits. In this study patients with high mean IOP had shorter times to progression. Patients with the highest mean IOP had the highest IOP fluctuation, whereas patients with low mean IOP had low IOP fluctuation. IOP fluctuations were no independent risk factor for the progression in or to glaucoma. The main difference compared to other studies was that post-progression IOP data were not included (20). Similar results were found by Medeiros et al. (21). Hopf et al. found out that IOP-fluctuations were no predictor for progression from ocular hypertension to glaucoma when treatment is already in place (22).

1.3.3 Glaucoma

Glaucoma is manifested by a typical optic neuropathy, with characteristic visual field loss, and may lead to blindness. The main risk factor for developing glaucoma is elevated intraocular pressure (23). Glaucoma is defined as progressive loss of retinal ganglion cells and characteristic changes in neuroretinal rim tissue in the optic nerve head accompanied by visual field constriction.(24)

1.3.3.1 Prevalence of Glaucoma

Worldwide: The number of people (aged 40–80 years) with glaucoma is estimated to be 76.0 million in 2020 and 111.8 million in 2040 (25).

Germany: Based on data of the Gutenberg Health Study is the prevalence of glaucoma 1.44% (people aged 35-74 years) (26).

The prevalence of Glaucoma increases with age (25–29). Worldwide Glaucoma is the second leading cause for blindness and number one cause for irreversible blindness (30).

1.3.3.2 Risk factors for developing Glaucoma

The risk for developing glaucoma rises with age (31–33), myopia (32), lesser central corneal thickness (33), larger vertical cup-to-disc (C/D) ratio (33) greater than 0.7 (31), larger vertical C/D ratio asymmetry (33), a


Discussion and Conclusion 62

low-fatigue HIIT > high-fatigue HIIT. The study by Conte et al. (Table 10, p. 14) showed that the decreasing effect on the IOP after the exercise lasted 5 minutes after moderate training and 10 minutes after the high-intensive interval training.

4.1.6 The Long-term Effect of Running Exercise on the IOP

A training program lasting 3 months included one hour of jogging per day on 5 days per week in addition to a playing hockey. The baseline IOP of the former sedentarians decreased by -1.37 mmHg after this program (Table 5). Vera et al. speculated that higher fitness may allow stabilization of the IOP response after exercise (48).

4.1.7 Flaws of the Findings

The discussed findings can´t be generalized as several studies were made with subjects with a mean age below 27 years. Further investigations should include subjects of older ages.

The comparability of the data out of the studies is limited since different devices of the measurement were used (80–82).

4.1.8 Conclusion

Running can generally be recommended as it has a decreasing effect on the IOP. This may be of interest for patients at risk for developing glaucoma or already suffering from it. Going through a training program for running may lead to a lower baseline or mean IOP. Also, it was shown that higher fitness led to a stabilization of the IOP: The effect of running on the IOP seems to get less with higher physical fitness. This should get into account when a highly fit person has an elevated IOP or signs of glaucoma regarding the decision finding if treatment should be recommended. On the other hand, people leading a sedentary live may benefit from regular running exercise and it´s lowering effect on the IOP while a moderate training keeps the IOP fluctuations low and may lead to a lower baseline IOP if practiced on a regular base.

In any case, it is recommended to have a general health check by a physician before starting an exercise program.

4.2 Discussion of Findings and Conclusion for Fitness/ Weight training A total of sixteen studies were reviewed regarding the effect of fitness/ weight training exercises on the IOP. On their basis the following is discussed:

• The Effect of Exercise Intensity on the IOP and the Role of Physical Fitness • Comparison of the Effect of Isometric and Isokinetic Exercise on the IOP • The Influence of Fitness/ Weight training of the Upper and Lower Limb on the IOP • The Influence of Fitness/ Weight training with and without Valsalva Maneuver on the IOP • Flaws of the Findings

At the end of this chapter a conclusion out of the discussed topics will be made.

4.2.1 The Effect of Exercise Intensity on the IOP and the Role of Physical Fitness

The following figures show the effect of exercise intensity of ballistic bench press (Figure 8) and jump squats (Figure 9) on the IOP. The study summarized in Table 22 (p. 25) gave the data for the high fit and the low fit group, while the values for the active group are out of Table 21 (p. 23).

Regarding the performance of ballistic bench press it was found that the higher the physical demand of this exercise the higher the effect on the IOP. Additionally, it can be seen that higher fitness calms the reaction of the IOP down compared the reaction of the IOP in subjects with lower fitness.


Discussion and Conclusion 66

4.2.6 Conclusion

Fitness and weight training leads to fluctuations of the IOP in a pronounced manner when performed at moderate and high intensity. Therefore only a moderate training can be recommended if there is need to keep the IOP stable. Isometric exercise can generally not be recommended as it provokes a rise of the IOP even when performed with light loads. Special attention should be paid to breathing during training. The Valsalva Maneuver should always be avoided. The IOP behaved more stable when higher fitness was present.

Before starting a training program, a physician and an eye care specialist should be consulted.

It might be interesting to ask patients with normal tension glaucoma if they have a history of prolonged weight training or other physically demanding hobbies or work. A retrospective study regarding this topic might give interesting data to understand the development of glaucoma in patients with normal IOP.

4.3 Discussion of Findings and Conclusion for Swimming/ Diving In this review one study investigating the behavior of the IOP during swimming is included (Table 31, p. 36). This study is therefore interesting showing that even after a prolonged and intense swimming relay the IOP seems to be stable, although one should keep in mind that only two measurements were taken. It can be said that the conditions in this study do not represent daily swimming exercises that are done for general health in a moderate manner. It would be interesting to see the behavior of the IOP during and after moderate swimming exercise, especially in elderly and glaucoma patients.

While swimming or diving the usage of googles is common. This may influence the IOP in addition to the exercise itself.

Swimming Goggle wear: An increase in intraocular pressure was observed while wearing swimming goggles (83–85). The size of the swimming goggles seems to play an important role: the smaller the swimming goggles, the greater the increase in intraocular pressure (84). On the other hand, Franchina et al. compared the data of 204 regular swimmers to 99 individuals who did not swim. They did not found a relation between swimming goggle wear and the prevalence of glaucoma (86).

Regarding the behavior of the IOP during diving, only one study simulating the conditions of a dive in a hyperbaric chamber could be found. This showed that the IOP decreased slightly but significantly at a pressure of 2 BAR, which is supposed to simulate a dive at 10 meters. It then remained stable for 60 minutes as long as the ambient pressure of 2 BAR prevailed (87).

Diving mask wear: In contrast to the behavior of IOP when wearing swimming goggles, a small but statistically significant decrease in IOP was observed when wearing a diving mask (88).

4.3.1 Conclusion

If swimming can be considered as a safe sport regarding the behavior of IOP remains difficult say due to the lack of studies. Same must be said for diving. However, the usage of googles should be handled with care and the size of these glasses must be well fitted to prevent elevation of the IOP.


Final Words 72

5 Final Words To my knowledge this review is the most detailed and transparent written about the influence of sports activities on the intraocular pressure. However, in a time where research publishes articles more or less in one after the other, it should be updated at given time and filled with new knowledge, hopefully with data of glaucoma patients and elderly subjects.


Appendix vii

Appendix


References viii

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2. Gale J, Wells AP, Wilson G. Effects of Exercise on Ocular Physiology and Disease. Surv Ophthalmol. 2009 May 1;54(3):349–55.

3. Zhu MM, Lai JSM, Choy BNK, Shum JWH, Lo ACY, Ng ALK, et al. Physical exercise and glaucoma: a review on the roles of physical exercise on intraocular pressure control, ocular blood flow regulation, neuroprotection and glaucoma-related mental health. Acta Ophthalmol (Copenh). 2018;96(6):e676–91.

4. Wylegala A. The Effects of Physical Exercises on Ocular Physiology: A Review. J Glaucoma. 2016 Oct;25(10):e843.

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8. Eye Pressure [Internet]. American Academy of Ophthalmology. 2018 [cited 2021 Feb 16]. Available from: https://www.aao.org/eye-health/anatomy/eye-pressure

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11. Liu JHK, Zhang X, Kripke DF, Weinreb RN. Twenty-four-hour intraocular pressure pattern associated with early glaucomatous changes. Invest Ophthalmol Vis Sci. 2003;44(4):1586–90.

12. David R, Zangwill L, Briscoe D, Dagan M, Yagev R, Yassur Y. Diurnal intraocular pressure variations: an analysis of 690 diurnal curves. Br J Ophthalmol. 1992 May 1;76(5):280–3.

13. Sobczak M, Asejczyk M, Geniusz M. Does body position, age, and heart rate induce IOP’s changes? Eur J Ophthalmol. 2021 Jun 6;11206721211023312.

14. Lee JY, Yoo C, Jung JH, Hwang YH, Kim YY. The effect of lateral decubitus position on intraocular pressure in healthy young subjects. Acta Ophthalmol (Copenh). 2012;90(1):e68–72.

15. Malihi M, Sit AJ. Effect of Head and Body Position on Intraocular Pressure. Ophthalmology. 2012 May 1;119(5):987–91.

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Declaration xiv

Declaration I declare that this thesis, which I submit to Aalen University for examination in consideration of the award of a higher degree M.Sc. Vision Science and Business (Optometry) is my own personal effort. Where any of the content presented is the result of input or data from a related collaborative research program this is duly acknowledged in the text such that it is possible to ascertain how much of the work is my own. I have not already obtained a degree at Aalen University or elsewhere based on this work. Furthermore, I took reasonable care to ensure that the work is original, and, to the best of my knowledge, does not break copyright law, and has not been taken from other sources except where such work has been cited and acknowledged within the text.

I would like to thank my supervisors for giving me the freedom to write this work as I did it.

Signed ___ ______________________

Student Number: 75125

Date: August 18th, 2021

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