Prevalence of UI
The prevalence of UI in this study (43.9%) was in the mid-range of UI experienced by athletes (5.56–80%) [3, 32] and at the upper limit experienced by women in the general population (25–45%) . Furthermore, the prevalence of UI in this cohort was higher than that found in similar studies investigating UI in competitive women weightlifters (31.9%) . Skaug et al., however, reported an even higher prevalence of UI (50%) in a combined cohort of competitive Norwegian weightlifters and powerlifters . Out of the women who reported experiencing UI in their study, 78.9% were powerlifters, and 21.1% were weightlifters. This may imply that the prevalence of UI was much higher in Norwegian powerlifters than weightlifters. However, the number of powerlifters in their study was more than double the number of weightlifters . When adjusted, relative to the number of participants in each cohort, UI was experienced by 56% of powerlifters and 36% of weightlifters. After adjusting for the number of participants, their findings still support our results that UI is experienced by more powerlifters than weightlifters. The exact mechanism for greater UI in powerlifters compared to weightlifters is not fully known. However, it is possible that powerlifters experience greater UI in training and competition as they lift greater loads. Indeed, our findings suggest that the higher prevalence of UI in powerlifters is primarily due to a higher prevalence of athletic incontinence.
The prevalence of athletic incontinence was higher in this study (23.1%) than in similar studies examining athletic incontinence in weightlifters (16.2%) . It is noteworthy, however, that the main difference was observed in type 1 athletic incontinence: weightlifters 8.4% , powerlifters 17.9%. This finding indicates that previously continent women who commence powerlifting are more likely than weightlifters to experience UI during training and competition but are not necessarily more likely to be incontinent during everyday activities. While UI during exercise may deter participation, athletic incontinence may be tolerated by women if leakage is minimal, only occurs infrequently, or at maximal effort, and they remain continent during everyday activities.
Parity, age and BMI were the risk factors in the general population that correlated with UI in this study . Competition total was the only sport specific risk factor found to significantly correlate with participants’ ISI scores. To further explore the correlation between ISI and general and sport specific risk factors, we divided our cohort into women who had given birth and women who had not given birth (Table 1). Interestingly, age, BMI and competition total were significantly correlated with ISI scores only in women who had not given birth. Giving birth is possibly the greatest risk factor for UI in women, hence, some younger women, who had given birth, also experienced UI. This could explain why UI in the cohort of women who had given birth was not correlated with age. Contrary to our findings, Skaug et al. performed a multivariate logistic regression and found that only BMI had a significant positive association with stress UI . It is difficult to explain the discrepancy in the findings, however, differences in participants and assessment tools may explain the different results. For example, Skaug et al. recruited a more homogenous sample of nationally and internationally competitive male and female powerlifters and weightlifters who competed at a higher level than our participants .
Sport Related Factors
Data pertaining to sport specific factors thought to contribute to the provocation of UI were collected based on the feedback from the pilot study  and the relevant literature. The three sport related factors of interest were: load, body position and fatigue.
Sport Related Factors—load
Our results showed that participants were more likely to experience UI during heavy lifts. Indeed, participants who lifted the most weight in competition experienced the most severe UI. The deadlift is the lift where powerlifters are likely to lift the greatest amount of weight, and correspondingly, the deadlift was the lift most likely to provoke UI (42.5%). Our results supported the findings by Skaug et al., who also reported that the deadlift was the lift most likely to provoke UI in competitive weightlifters and powerlifters . The squat was the second most likely competition lift to provoke UI in our cohort of powerlifters. While 36.3% of participants in our study reported experiencing UI during squats, comparable studies reported that 23% of weightlifters  and 12.6% of CrossFit participants  experienced leakage of urine while squatting. Squats are possibly less likely to provoke UI in weightlifters and CrossFit participants due to a difference in the amount of weight lifted, and the number of sets and repetitions performed during training or competition. The primary goal of CrossFit training is to develop fitness as well as strength, and while CrossFit participants may occasionally work up to a One Repetition Maximum (1-RM), this is not the exclusive aim of the sport. Weightlifters are more likely than CrossFit participants to perform sets of squats with heavier weights to develop their strength rather than endurance. While powerlifters also focus on gaining strength, they are likely to train with heavier weights than weightlifters and perform sets with fewer repetitions to lift the maximum weight possible during a single repetition. Despite small variations in squat technique between powerlifters, weightlifters and CrossFit participants, it is possible that the prevalence of UI is influenced by the total weight lifted. We note however, that while lifting a progressively heavier weight has been shown to increase intrabdominal pressure , it is more difficult to demonstrate that lifting heavy weights provokes UI [15, 33].
Interestingly, some of the powerlifters in this study and the pilot study  reported that with progress in training capacity, they were able to lift heavier weights without leaking. An increase in UI threshold and urinary leakage were only experienced at near or above their previous maximum lifts. In other words, they were still incontinent, just at a higher lifting weight.
Sport Related Factors—Body Position
In addition to the total amount of weight lifted, some women reported that other factors such as body position during lifts provoked UI. Body position while lifting a weight has been found to influence the amount of intra-abdominal pressure , a phenomenon thought responsible for leakage during physically exerting actions. In our study, the bench-press, in comparison to the two standing lifts, was very unlikely to provoke urinary leakage. This finding supports the recommendation of low impact activities that do not place downwards pressure on the pelvic floor when the aim is to prevent UI during sport and exercise . While the bench-press is usually the lift where the least amount of weight is lifted, women still lift a significant amount of weight with some women lifting more than double their own body weight.
Body position during the deadlift was also problematic for some women who reported that sumo deadlifts, where the lifter has a wider stance compared to the conventional deadlift, were more likely to provoke UI. The possibility that sumo deadlifts provoke UI in some powerlifters has been identified in a previous study . Wearing a lifting belt and exercises that put further pressure on the abdominal area such as sit ups and front squats were reported to be problematic for some women.
Sport Related Factors—Fatigue
Pelvic floor muscle fatigue can exacerbate UI, especially stress UI . Our participants reported that fatigue provoked UI if they were not well rested before a training session, their sets were long and/or heavy and if individual lifts were difficult and slow. A little over a third of the women experienced leakage during high repetition sets, especially at the end of heavy sets, indicating that not only the amount of weight lifted and body position but also fatigue played a part in the provocation of UI in this cohort of powerlifters. One explanation why fatigue contributes to UI in women athletes is that women training at a competitive level may have a stronger pelvic floor than non-trained women but less pelvic floor muscle endurance .
Activities Found to Provoke UI and Self-care Activities
Furthermore, participants in this study provided an extensive list of activities that they felt provoked UI (Table 2). The activities specific to powerlifting that provoked UI were focused on bracing, lifting technique and how they wore their belt. Outside powerlifting training jumping or skipping movements were the most problematic activities. Research with CrossFit participants have found that the cardio component of training sessions such as running and skipping is more likely to provoke UI in women than lifting weights [36, 37]. Many women were conscious of the amount of fluid that they consumed prior to lifting, and some would limit fluids prior to training or competition or even train dehydrated. Minimising fluid intake to manage UI during physical activity had previously been reported [36, 38].
Participants in this study also provided an extensive list of training and competition related strategies utilised to prevent, reduce or contain leakage. Many self-care strategies revolved around warming up for training or competition, correct set up, activation of the pelvic floor and focusing on technique and bracing. A more detailed list of responses is available in Table 3. It is noteworthy that there is very little or no research specific to powerlifting and strategies to prevent or minimise leakage of urine during training or competition. The women were therefore relying on their own experience, the internet or expert opinion rather than evidence-based practice. Practice is preceding research in this area and consequently coaches, trainers, physiotherapists and medical professionals who support women powerlifters are largely relying on trial and error and research that is not powerlifting or even sport specific. While our study is descriptive and cannot assign causation, it will increase the knowledge of UI in competitive women powerlifters and help form a foundation for future research.
Pelvic Floor Exercises and Pelvic Exams
Most of the participants in this study reported that they were confident in their ability to perform pelvic floor exercises. It has been shown, however, that depending on the population being studied as many as 15.1–65% of women do not know how to correctly perform a pelvic floor contraction [39,40,41]. A total of 68 participants in this study had undergone a pelvic floor examination and therefore, most women had not had their ability to generate an effective, timely pelvic floor contraction assessed. Having undergone a pelvic floor examination or being confident in their ability to perform pelvic floor exercises were both negatively correlated with ISI scores suggesting that these subgroups of women experienced less severe UI. This finding supports the recommendation that athletes undergo a pelvic floor assessment and have their ability to correctly perform pelvic floor exercises confirmed .
While valuable information was provided by a large cohort of women powerlifters, it is important to acknowledge that this study had some limitations. Firstly, our study used a cross sectional design to identify the association between risk factors and UI. This design fails to assign and investigate causation. Secondly, it was not possible to avoid potential survivor bias when considering the relationships between UI and powerlifting. Secondly, the recruitment of participants through social media and by email may have introduced further bias as women who have experienced UI may have been more interested in completing the survey. The women also relied on recall when answering the survey questions, as opposed to being evaluated based on an objective measurement. Despite these limitations, this study builds on the knowledge obtained in the pilot study and greatly increases understanding within this niche area. The results from this study form an important basis for future studies in an under-researched topic.