Evaluating Pelvic Floor Dysfunction in Female Horse Show Jumpers Using the Australian Pelvic Floor Questionnaire

Introduction

Pelvic floor dysfunction (PFD) is characterized by anatomical and functional disorders caused by damage to support structures [1–3]. The overall prevalence of PFDs among professional female athletes was 45.1% [4], and was more prevalent in high-impact sports like horse show jumping [5,6]. Two different hypotheses are found in the literature regarding the benefits of sports activity on pelvic floor function [7]. The first assumes a positive effect of physical activity on the pelvic floor muscles (PFMs) by strengthening them through co-contraction, which could prevent dysfunctions such as the descent of organs and urinary and fecal incontinence [7]. Excessive muscle tension can contribute to pelvic floor dysfunction and make effective relaxation difficult, for example during childbirth [7]. The opposing hypothesis assumes that sports activity can contribute to overload and overstretching of the PFMs. This is supported by the increased intra-abdominal pressure which, in the absence of adequate contraction of the PFMs, can cause overstretching of pelvic floor structures and lead to its dysfunctions [7].

There are publications in databases on the effects of horseback riding on motor function, muscle tone, and body posture, and relating to the therapeutic effect of horseback riding (hippotherapy) [8,9]. Some reports also refer to the incidence of injuries and the most common injuries among horseback riders [10]. However, there is little literature on the effects of horseback riding on pelvic floor function, and the available literature is only concerned with recreational riding on flat ground. In the collected literature, studies have shown that recreational horseback riding does not predispose to dysfunction within this body region [11–13]. In one publication, the authors presented the results of research suggesting that, if combined with appropriate PFM exercises, recreational horseback riding can help prevent dysfunction [11]. Despite the widespread belief among medical professionals that horseback riding has a negative effect through excessive tension of PFMs and obstructed labor, the available scientific studies have not demonstrated a link between horseback riding and complications during labor [14]. However, studies are showing that high levels of saddle pressure on the rider’s perineal area can contribute to tissue compression, inflammation, degeneration, and micro-trauma in the pelvic area [15].

When riding in a show jumping course, the rider and horse must overcome a series of obstacles. During different phases of the jump, the rider changes position in the saddle, and after the jump the pelvis returns to the saddle [16]. However, analysis of electromyography (EMG) muscle activation in lower-body muscles shows constant activation of muscles even if kinematics changes were observed during different jumps, which means poorer muscle coordination [17]. The specific nature of this equestrian sport suggests that altering muscle tone in the pelvic floor and with the occurrence of high levels of impact and shock can predispose to PFM dysfunction [18].

Horse show jumping is gaining more and more popularity among other equestrian sports [19,20], but in the literature we reviewed, no studies were found that examined whether there was a relationship between the equestrian discipline of show jumping and PFM function, which was the starting point for the study. The aim of the present study was to assess the effect of horse show jumping on pelvic floor dysfunction in women.

Material and Methods

ETHICS:

The ethics criteria were met. Participation in the study was voluntary. Written informed consent to participate in the research was obtained from all participants. They were informed about the purpose and experimental procedure and the possibility of withdrawal from the study. The participants were informed that no third parties will have access to the data collected in the research process and that the data will be used solely for scientific reasons, including presentation at conferences and publications in scientific journals. The data were processed anonymously. The rules of General Data Protection Regulation (GDPR) and International Conference of Harmonization/Good Clinical Practice (ICH/GCP) and other applicable laws were met and respected during data collection, storage, and analysis. The replies obtained from the participants were secured and stored at the Department of Rehabilitation of Józef Piłsudski University of Physical Education and were archived in a password-protected computer with limited access. The research received approval from the Senate Ethics Committee for Scientific Research (SKE 01-39/2023) and was conducted according to the Declaration of Helsinki.

RESEARCH QUESTIONS AND HYPOTHESIS:

To achieve the study aim, the following research question was developed: What is the effect of horse show jumping on pelvic floor dysfunction in women?

The main question was supported with detailed questions: a) Does show jumping in horse riding affect pelvic floor dysfunction in women? b) Does pelvic floor function efficiency differ between women who train and those who do not train for horse show jumping? c) What is the correlation between sociodemographic characteristics of women with past, current, and no history of horse show jumping?

The following hypotheses were defined: a) Horse show jumping affects pelvic floor dysfunction in women, b) The pelvic floor muscle function efficiency differs between women who train and those who do not train for horse show jumping, and c) Sociodemographic features affect pelvic floor dysfunctions in women.

DESIGN AND SAMPLE:

A quantitative study was conducted and an observation approach was chosen. Comparison of 2 groups was performed. The cohort group was composed of females who were practicing show jumping currently and in the past for at least 1 year, at least once a week, in good health, and without general systemic conditions. The control group were female non-riders who were healthy and without general systemic conditions.

The sample size calculation was conducted using G*Power (version 3.1) for a one-way analysis of variance (ANOVA) with fixed effects. Assuming a medium effect size (ƒ=0.25), an alpha level of α=0.05, and a desired statistical power of 0.80, a total sample size of 159 participants was determined as sufficient to detect statistically significant differences among 3 groups. The current study includes 160 participants, exceeding the calculated requirement and ensuring adequate power (actual power=0.804) for the analysis.

INCLUSION AND EXCLUSION CRITERIA:

The inclusion criteria for the study group were practicing show jumping for at least 1 year, show jumping training at least once a week, females in good health, and without general systemic conditions. The inclusion criteria for the control group were female non-riders, and healthy women without general systemic conditions. The exclusion criteria for study groups I and II and the control group were male sex, pregnancy, previous childbirth, previous abdominal or genital surgery, age below 18 years, menopause, smoking, BMI >25kg/m², diagnosed cardiovascular, respiratory, nervous system disorders, metabolic, renal, gynaecological, mental disorders, and current injuries and trauma to the musculoskeletal system.

QUESTIONNAIRES:

The study was conducted using 2 survey questionnaires: the custom-designed survey questionnaire, and a validated questionnaire, the Australian Pelvic Floor Questionnaire (APFQ) [21,22].

The custom-designed survey questionnaire was designed to include female participants in the study. It contained questions on inclusion and exclusion criteria, anthropometric characteristics (age, body height, body weight), and lifestyle (additional physical activity, frequency of alcohol consumption, smoking). For the participants in the study group, the questionnaire was extended to include questions about the sport practiced (show jumping), such as frequency of training and training experience.

The Polish version of the validated survey questionnaire APFQ was used to assess PFM function. The questionnaire is made up of 4 sections assessing bladder function, bowel function, descent of the reproductive organs, and sexual function. Individual questions are scored on a 4-point scale (0 meaning no dysfunction and 3 meaning the dysfunction to the highest degree). Each section also includes a question about the degree to which the dysfunction causes suffering, with 0 meaning not at all and 3 meaning very much. Bladder function is assessed using 15 items on a scale of 0 to 3 (max. 45 points), bowel function is assessed using 12 items on a scale of 0 to 3 or 0 to 2 (max. 34 points), descent of the reproductive organs is assessed with 5 items on a scale of 0 to 3 (max. 15 points), sexual function is assessed with 10 items of which 6 are scored on a scale of 0 to 3, one on a scale of 0 to 2 and one on a scale of 0 to 1 (max. 21 points), and 2 items are not scored, concerning sexual activity and the reason for its possible absence. Scores are calculated separately for each section and divided by the number of maximum points and then multiplied by 10. Next, each function examined is scored from 0 to 10. The maximum number of points to be scored is 40, and for sexually inactive women, it is 30 points (some of the scored items do not apply to sexually inactive women) [21,22].

DATA COLLECTION PROCESS:

The data were collected between January and April 2023. The surveys were conducted online and anonymously. Information about the survey in the form of an information leaflet with a link to the questionnaire was posted on specialist online forums for show jumpers. Questionnaires for female participants from the control group were delivered via instant messaging and websites. We received 395 replies; 160 responders met the inclusion criteria and were included in the study in cohort and control group. For both groups, it was possible to receive the results and interpretation of the examination, for which the participant’s data were encoded and a message was sent to the email provided. Six women requested to receive the results of the examination with interpretation.

STATISTICAL ANALYSIS:

To verify the research hypothesis, qualitative and quantitative data were analyzed. Statistical analysis of the results obtained in the study was carried out using Statistica 13.3 and Excel software (Microsoft 365). Quantitative data are presented as descriptive statistics using measures such as arithmetic mean and standard deviation. Qualitative data are presented in percentage terms. The Shapiro-Wilk test was used to examine data in terms of normality of distribution. Since the condition on the normality of distributions was not met, the Mann-Whitney U test was used to analyze the differences between the 2 groups, and ANOVA and its non-parametric equivalent, the Kruskal-Wallis test, were used to analyze the differences between the 3 groups. The level of statistical significance was set at p<0.05.

Results

PARTICIPANTS CHARACTERISTIC:

The study included 160 healthy and physically active women aged 23.69±3.96 years, with body weight of 58.5±7.14 kg, body height of 167.24±6.50 cm, and BMI of 21.04±1.86 kg/m2. Study group I consisted of 55 women actively participating in show jumping, with 17 participants declaring that they had participated in competitions. Study group II consisted of 19 women who had trained in show jumping in the past. The control group consisted of 86 women not practicing any form of horseback riding. Age, body weight, height, and BMI showed small to negligible effect sizes, accounting for minimal variability (less than 4%) in group differences. In contrast, training experience and frequency demonstrated very large effect sizes, explaining substantial proportions of variability (62% and 67%, respectively). Details of the study participants (by group) are presented in Table 1.

Based on the authors’ survey questionnaire, a significant correlation was found between participation in show jumping training and level of education (p=0.001) and place of residence (p=0.015). The strength of the relationship was weak, with a Cramer’s V coefficients of V=0.263 and V=0.244, respectively. There was no significant relationship between show jumping training and the frequency of alcohol consumption (p=0.902) or the occurrence of menstrual cycle disorders (p=0.701). Detailed results are presented in Table 2.

PHYSICAL ACTIVITY ASSESSMENT:

The percentage of women undertaking additional physical activity was 45% (n=25) in group I, 63% (n=12) in group II, and 69% (n=59) in the control group. Irregular (less than once a week) additional physical activity was undertaken by 12% (n=3) in group I, 8% (n=1) in group II, and 14% (n=8) in the control group. None of the women in study group I (show jumping) undertook additional physical activity more than 4 times a week or more frequently. It was impossible to assess the relationship between show jumping training and the frequency of additional physical activity due to the low number of responses.

The most common additional physical activity undertaken was gym training (33% in group I and 25% in group II) in both study groups, and yoga (32%) in the control group. Detailed characteristics of various types of physical activity undertaken by groups is shown in Figure 1.

PELVIC FLOOR DYSFUNCTION ASSESSMENT:

Based on the results of the APFQ questionnaire, there were no statistically significant differences between the study groups in any of the PFM functions examined by the questionnaire: bladder function (p=0.901), bowel function (p=0.266), descent of the reproductive organs (p=0.626), sexual function (p=0.515), and the total score obtained (p=0.460 for sexually active women and p=0.834 for sexually inactive women). In the section assessing bladder function, the highest score, 0.93±0.85 points, was observed in group I, in the section assessing bowel function, the highest score of 1.38±0.93 points was obtained in group II. In the section assessing the descent of organs, the highest score was observed in the control group (0.04±0.19 points), and in the section on sexual function, the highest score of 1.80±1.40 points was also found in the control group. Eleven women in study group I, 2 in study group II, and 17 women in the control group were sexually inactive. For sexually active women, the highest score for the entire questionnaire was 4.19±2.09 points for the control group, while for sexually inactive participants, the highest score of 2.20±1.39 points was recorded for study group I. Bladder function, bowel function, prolapse symptoms, sexual function, and total score (inactive) showed negligible to very small effect sizes, indicating minimal or no meaningful differences between groups. However, total scores (active) demonstrated a medium effect size, explaining approximately 5% of the variability. Detailed results are shown in Table 3.

BLADDER FUNCTION ASSESSMENT:

In the section assessing bladder function, the most frequently reported problem was imperative urinary urgency, declared by 55% (n=30) of women in group I, 68% (n=13) in group II, and 50% (n=43) of those in the control group. The highest possible score (3 points) for this section was achieved by only 1 person in Group I and 1 in the control group. The maximum possible score was also obtained by the participants in the item on residual urinary retention (1 participant in each group), the use of sanitary pads due to involuntary urine leakage (1 participant in group I and 3 in the control group), urinary incontinence (1 participant in the control group), and the item on recurrent urinary tract infections (2 participants in group I, one participant in group II). Impaired functioning due to perceived problems to the highest degree was reported by only 1 person in the control group. Suffering at the highest rated level was reported by 1 person in group II and 1 person in the control group. Detailed results for the various aspects assessed in terms of bladder function by group are shown in Figure 2.

BOWEL FUNCTION ASSESSMENT:

In the section assessing bowel function, the most frequently reported problem in each group was straining at stool, declared by 88% (n=43) of women in group I, 95% (n=18) in group II, and 81% (n=70) of those in the control group. The maximum possible score (3 points) was achieved by 3 participants in group I and 2 participants in the control group. Maximum scores were also obtained by the participants in the following items: constipation (1 person in group I, 1 person in group II), fecal urgency (1 person in group II), incomplete defecation (1 person in group I and 1 in the control group), and manual assistance with defecation, reported by 1 person in study group II. Suffering at the highest rated level was reported by 1 person in group II and 3 people in the control group. Detailed results for the various aspects assessed in terms of bowel function by group are shown in Figure 3.

DESCENT OF REPRODUCTIVE ORGANS:

In the section on descent of reproductive organs, the most frequently reported problem was the feeling of a foreign body in the vagina, declared by 2% (n=1) of the women in group I and 2% (n=2) in the control group. Participants scored a maximum of 1 point. Descent of the organs was reported by 1 person in group I, scoring 1 point, and repositioning for defecation was reported by 1 person in the control group, scoring 2 points. None of the women in group II declared problems related to descent of the reproductive organs. Suffering at a level rated at 1 point was reported by 1 person in the control group. None of the questions scored 3 points and the highest score achieved in the section was 2 points. Detailed results for the various aspects assessed in terms of descent of the reproductive organs by group are shown in Figure 4.

SEXUAL FUNCTION ASSESSMENT:

In the section on sexual function, the largest number of female participants reported the problem of dyspareunia: 57% of women in group I (n=25), 59% in group II (n=9), and 74% in the control group (n=51). The maximum possible score (3 points) on the dyspareunia item was obtained by 2 women in group I, 1 in group II, and 1 in the control group. The question on insufficient vaginal lubrication was scored by 7 women in group I and 20 in the control group. Maximum scores were also obtained by the participants in the questions on altered vaginal sensations during intercourse (3 participants in group I, 1 participant in group II), on tight vagina - vaginismus (2 participants in group I, 1 participant in group II, 2 participants in the control group). Suffering at the highest rated level was reported by 2 women in group I and 1 in the control group. Detailed results for the various aspects assessed in terms of sexual function by group are shown in Figure 5.

Discussion

PRACTICAL IMPLICATIONS:

Our research on horse show jumping and its impact on the pelvic floor dysfunction in women represents a pioneering investigation into pelvic floor dysfunction among female show jumping riders and offers crucial insight that highlights the need for increasing the awareness of proper PFD care. Education is needed on bladder, bowel, sexual functions, and descent of the reproductive organs followed by development of new patient-centred protocols, and urogynecology physiotherapists should promote self-management techniques and active involvement of women in the rehabilitation process. Since many women are reluctant to discuss PFD, knowledge in this area needs to be further developed.

LIMITATIONS:

In the present study, several limitations can be identified that are worth considering when planning further research in this field. The APFQ questionnaire is a validated research tool successfully used among professionals and researchers [30,31]. However, it should be noted that the form of the survey itself (an online survey) carries the risk of unreliable results. The participant may misunderstand the questionnaire items and thus provide inadequate responses. Perhaps using a web-based version of the questionnaire completed in the presence of the researcher would reduce errors due to misunderstanding of the content of the questionnaire. It would also be advisable to carry out a survey supplemented by manual examinations and objective measurements based on a clinical examination, or the increasingly popular ultrasound examination which, unfortunately, poses a challenge given the low number of women declaring themselves willing to undergo a per vaginum examination. To date, no studies have been carried out on people already showing pelvic floor dysfunction or on menopausal women, which is also an issue worth addressing in future studies.

A strength of the study is that a validated and specific research tool for assessing PFM function (the APFQ questionnaire) was used. Participants were included in the study according to strict inclusion criteria to control confounding variables other than show jumping that could affect the results. Analysis of additional confounding variables such as riding experience, training intensity, and additional physical activities should be analyzed more in depth in the next stage of the research. However, this translated into a significant reduction in the number of women included in the study and differences in numbers between groups. The statistical analysis of the total score of the questionnaire considered the division between sexually active and sexually inactive women.

Conclusions

Pelvic floor dysfunction does not differ between show jumping riders and non-riders, so further research is advisable in this field, considering different equestrian sports and the use of clinical assessment of PFM function. The present study contributes to filling the knowledge gap and is important to the development of urogynecology physiotherapy.