In recent decades, Para athletes have gained greater prominence and have increasingly participated in a wide range of events (Baumgart et al., 2022). Therefore, there have been growing concerns about the necessity for advanced physical fitness and comprehensive training technique knowledge to optimize performance in athletes with physical impairments (Gee et al., 2021; Rodríguez Macías et al., 2022). Although contemporary studies have explored training methods for wheelchair sports (Simim et al., 2017; Baumgart et al., 2018), research has remained limited on competitive sporting disciplines outside the context of the Paralympic Games (Lexell and Frontera, 2023).

In this regard, waterskiing, a popular towed water sport activity, has provided leisure opportunities for individuals with spinal cord injury (SCI) (Urbański et al., 2021); and caters to various ability levels, including those who cannot stand (Suárez-Iglesias and Villa-Vicente, 2017). In the discipline of slalom, whether for athletes in the seated division or those able to stand, success hinges on mastering a repeatable technique that reduces load during the deep-water start (DWS) and on executing DWS with precision (Bray-Miners et al., 2012). This process entails navigating a sharp increase in tow rope tension, which can surge to 2.0–2.5 times an athlete’s body weight (Keverline et al., 2003; Runciman, 2011). Lighter athletes may face even higher relative peak tensions, with skill level additionally influencing this tension (Suderman et al., 2023; Lance, 2024). Overcoming this significant initial tension requires considerable upper-body strength and endurance, especially for seated slalom athletes who primarily rely on their upper-body muscles to transition from water to a seated skiing position (Suárez-Iglesias et al., 2019b). To mitigate grip force and fatigue that may arise from maintaining the connection to the boat and control of tension on the line (Woodgate et al., 2021), various DWS methods are employed, including instructor-assisted starts and specific learning aids (USA Water Ski Level 1 Instructor’s Manual, 2012).

However, research on the experiences of seated slalom athletes with the DWS has been limited. For the development of an effective and efficient DWS, incorporating sport science principles that address the physiological processes activated during exercise is crucial (Hoffmann et al., 2014). Collecting data on the physical workload of seated slalom athletes may potentially enhance coaches’ ability to individualize training programs. This targeted approach could lead to more precise management of an athlete’s physical workload, potentially aiding in the effective monitoring and development of the athlete. Such an approach might also contribute to improved sports performance and could possibly reduce the risk of injuries and illnesses (Stieler et al., 2023).

In this context, recent studies have specifically investigated the experiences and physiological impacts on athletes engaged in seated slalom waterskiing. The first study, involving three males with paraplegia, found that recreational seated slalom waterskiing generally entailed moderate intensity, with an average heart rate (HR) reserve around 45% (Suárez-Iglesias et al., 2019a). The second study engaged five adults from a rehabilitation center with various physical impairments in a beginner’s seated slalom waterskiing course, and explored participants’ perceptions of wellness, learning, and enjoyment. It reported that session intensity varied from “fairly light” to “somewhat hard” on the original Borg Rating of Perceived Exertion (RPE) scale 6–20 (Suárez-Iglesias and Villa-Vicente, 2017). While these studies employed HR and RPE metrics— common tools in athletic performance monitoring for wheelchair sports (Simim et al., 2017) —their focus diverged from typical performance evaluations in practices, where HR and RPE-based training zones are benchmarks for coaches to assess and monitor athletes’ seasonal progress (Rodríguez-Marroyo et al., 2012; Yanci et al., 2015). Instead, these studies have highlighted broader aspects, such as the health benefits and inclusivity of participating in seated waterskiing for leisure.

Furthermore, tailoring training to an athlete’s stress levels, as indicated by grip force, can enhance training outcomes, according to Sahar et al. (2022). Handgrip strength, a common indicator of physical performance in adaptive athletes (O’Connor et al., 2022), warrants close attention, particularly in seated slalom athletes. Supporting this observation, research including a study with four males at a national championship revealed that seated slalom waterskiing significantly reduced handgrip strength. Notably, the degree of this reduction varied according to each athlete’s level of competition and overall fitness (Suárez-Iglesias et al., 2019b). Consequently, these findings suggested that monitoring handgrip strength could be instrumental in customizing training programs to optimize the performance and wellbeing of seated slalom athletes.

In light of the scenario previously outlined, this case study addressed the need for specialized training programs and an in-depth understanding of the physiological demands in seated slalom waterskiing. This research is centered around a young male athlete with SCI. It is methodically structured with a threefold objective: first, to quantitatively evaluate the efficacy and efficiency of both traditional and alternative DWS methodologies tailored to his specific condition; second, to analyze his exertion levels using HR zones and session-RPE (sRPE) for a comprehensive assessment of TL; and third, to assess his peripheral muscle fatigue, emphasizing handgrip strength measurements.

This case study contributes valuable perspectives on seated slalom waterskiing training for athletes with physical impairments, specifically focusing on an individual with paraplegia. It explores the potential effectiveness and efficiency of various DWS techniques, both traditional and alternative. Additionally, the study assesses impacts on internal TL, and handgrip strength during DWS and ongoing seated slalom activities.

In waterskiing, which demands considerable physical fitness and advanced skills (Mullins, 2007; Woodgate et al., 2021), the current study’s comparison of ADWS versus TDWS offers insightful observations, especially for coaches and athletes with SCI in seated slalom waterskiing programs. The analysis of effectiveness and efficiency suggests that ADWS, achieving a 100% success rate, may provide greater reliability and control – essential in this complex maneuver, especially when using adaptive equipment in extreme sports (Allen et al., 2021). Conversely, despite being faster, TDWS shows a lower success rate of 20%, potentially leading to athlete frustration, interruption of practice continuity, and a heightened risk of energy depletion and injury. These findings could inform training strategies that prioritize a balance between performance, safety, and technical skill (Gunderson, 1991; Suárez-Iglesias et al., 2019b), while acknowledging the sport’s challenging learning curve, the need for mastery over specialized equipment, adaptability to various environments, and the diverse components and time management within both standing and seated slalom waterskiing sessions (Thye and Rokosz, 1991; Bray-Miners et al., 2015; Suárez-Iglesias et al., 2019a).

Regarding HR monitoring for gauging exercise intensity, the current research found the participant primarily engaged in aerobic metabolism during seated slalom waterskiing sessions, evident from the predominant time spent in HR zones 1 and 2, similar to standing slalom waterskiing (Mullins, 2007) and paralleling findings in Para alpine skiing (Goll et al., 2015). Such data suggest moderate physical strain in seated slalom waterskiing, consistent with prior research in this discipline (Suárez-Iglesias et al., 2019a). This pattern can likely be attributed to the intermittent nature of the sessions, which, in both previous and current studies, involve seated slalom waterskiing sessions exceeding 10 min but interspersed with rest periods and varied training components, such as open-water practice and inner-slalom course practice.

In addition, this research records for the first time %HR_max values during DWS, ranging from 63.2 to 81.3%. These reflect slalom waterskiing’s high static and low dynamic demands (Mitchell et al., 2005) and are comparable to HR patterns reported in Para alpine skiing athletes (Goll et al., 2015). The comparable short duration of these activities, akin to the 55 s Para alpine skiing giant slalom runs, may explain these figures. Moreover, the similarity in HR responses between the seated slalom athlete during DWS and athletes in wheelchair tennis or basketball (Roy et al., 2006; Barfield et al., 2009; Croft et al., 2010; Sindall et al., 2013) further highlights the shared intermittent nature of these sports.

This investigation is the first to explore RPE in seated slalom waterskiing. The findings showed that the intensity of seated slalom waterskiing sessions ranged from moderate to fairly hard, according to the RPE categories defined by Rodríguez-Marroyo and Antoñan (2015). These RPE values, exceeding 5 on several occasions, suggest that the participant found the activity to be quite challenging. This contrasts with a study on elite wheelchair tennis athletes who reported lower RPE during singles matches (Sánchez-Pay et al., 2016), possibly due to differences in skill and experience levels. Evidence in the literature supports these findings, showing that perceived exertion can be influenced by skill level, as seen in recreational alpine skiers with advanced abilities reporting lower exertion (Scheiber et al., 2009).

It is now well established that TL monitoring is crucial for understanding an athlete’s adaptation to training and assisting coaches in program design (Halson, 2014; Simim et al., 2017; Rodríguez Macías et al., 2022; Stieler et al., 2023). The present study revealed differing TL scores when using HR and sRPE-based methods. The TL values obtained in this study were lower than those reported for wheelchair basketball athletes during small-sided games (55.3–67.5 AU) (Iturricastillo et al., 2017) and notably less than TL reported in elite wheelchair rugby athletes (247 ± 74 AU) using the same HR-based method (Paulson et al., 2015). These differences may stem from the distinct intensities and activities in wheelchair sports, characterized by high-intensity, intermittent wheelchair use, and varying eligible impairments (with wheelchair basketball encompassing diverse physical impairments and wheelchair rugby often involving athletes with cervical SCI). The sRPE-based TL values from this study were higher than those in wheelchair basketball for small-sided games (99.3 ± 26.9 AU) (Iturricastillo et al., 2017) but lower than in wheelchair rugby practice (934 ± 359 AU) (Paulson et al., 2015). These variances emphasize the need for cautious interpretation, considering differences in participant characteristics, activities, and training session durations across studies.

The intersection of objective and subjective measures in TL assessment for athletes with physical impairments is a topic warranting further exploration. The current research noted a moderate, yet non-significant, correlation between HR and sRPE-based TL (r = 0.45; p = 0.37) underscores the nuanced nature of seated slalom waterskiing’s static demands, particularly for individuals with paraplegia. In such instances, HR typically shows modest increases during fatiguing isometric exercises, a response linked to central factors (Petrofsky, 2001). Besides, the sRPE scores in this study, encompassing both central and peripheral inputs (Borg, 1982), might have been influenced by these factors. Firstly, the repetitive nature of DWS and the prolonged duration of seated slalom waterskiing sessions, often surpassing the typical 15 min waterskiing times on slalom courses (Mullins, 2007), could have resulted in heightened central fatigue in the participant. Secondly, the requirement for meticulous force adjustments and reactions to external disturbances in seated slalom waterskiing could have additionally contributed to peripheral muscle fatigue (Ferguson, 2010). The findings of this study are consistent with research indicating small or trivial correlations between HR and sRPE-based TL in wheelchair basketball (range r = − 0.30; ± 0.27 to 0.26; ± 0.28; p > 0.05) (Iturricastillo et al., 2017) yet they diverge from studies showing stronger correlations in wheelchair basketball matches (r = 0.63–0.65, p < 0.001) (Iturricastillo et al., 2016) and wheelchair rugby training sessions (r = 0.81) (Paulson et al., 2015). These variations might arise from differences in functional abilities among participants or diverse settings (e.g., small-sided games, training sessions, matches) in different studies.

The present research observed a significant decline in handgrip strength post-session, likely due to the intense engagement of finger flexors and forearm extensors required in tow rope handling (Mullins, 2007). This finding echoes a previous study (Suárez-Iglesias et al., 2019b), which showed an 18.5% average decrease in maximum handgrip strength among four seated slalom waterskiing athletes with SCI after 14 waterskiing sessions, typically after about 20.5 min of grip time. Comparable reductions are noted in judo, which similarly demands extensive use of these muscles (Bonitch-Góngor et al., 2012). In slalom waterskiing, gripping technique also influences forearm muscle load (Rosa et al., 2016); thus, we recommend coaches prioritize optimal upper limb positioning to improve neuromuscular performance in seated slalom waterskiing. Specifically, the ADWS technique, starting with a parallel grip on “the boom,” may offer advantages over TDWS tow rope handling from the outset of the maneuver. Future research should encompass a broader group of athletes across multiple seated slalom waterskiing sessions, focusing on a detailed comparison of grip strength pre- and post-successful DWS using both ADWS and TDWS.

Despite its contributions to research for sports for people with physical impairments (Liu et al., 2022), the study is not without limitations. Primarily, the reliance on a single participant restricts the generalizability of the findings to the broader population of athletes with SCI (Rayes et al., 2022). It is important to acknowledge that the limited participation of athletes with SCI in research inherently restricts the breadth of training recommendations, which often rely on the anecdotal experiences of coaches, athletes, and scientists (Perret, 2017). Additionally, the lack of a time-motion analysis, which would provide external training load metrics like distance, speed, and duration (Stieler et al., 2023) limits a more holistic understanding of the participant’s TL.

For intermediate-advanced seated slalom athletes with paraplegia, initially focusing on ADWS, despite being slightly more time-consuming than TDWS, provides a reliable foundation that leads to a higher number of successful water exits. This allows coaches to allocate more time to other essential waterskiing skills, such as those typically practiced during open-water skiing and navigating the inner-slalom course (e.g., crossing the wake and making precise turns). Once athletes are consistently successful with ADWS, coaches can gradually incorporate TDWS into their training sessions, as it is the DWS required for sanctioned events. This balanced approach, involving both DWS techniques and comprehensive training in all technical aspects of waterskiing, facilitates continuous and holistic athlete progression towards the competitive level.

Future research should investigate the long-term effects of integrating ADWS before transitioning to TDWS on seated slalom athletes with paraplegia. Evaluating key performance indicators such as skill acquisition speed, maneuver completion rates, athlete confidence, and injury incidence can provide valuable insights. This research could optimize training protocols, enhancing both the efficiency and safety of athlete development in competitive seated slalom waterskiing.

In conclusion, this study sheds new light on seated slalom waterskiing by comparing two DWS techniques for an athlete with SCI. The findings suggest that ADWS, with its full success rate, appears more effective but slightly more time-consuming than TDWS, which presented more challenges and fewer successes for the participant. The moderate TL during seated slalom waterskiing was perceived as a hard effort by the athlete with paraplegia, and the significant reduction in handgrip strength post-session underscores the discipline’s grip strength requirements. These insights enrich understanding of the technical, physiological, and physical demands in mastering DWS in seated slalom waterskiing, offering valuable guidance for coaches and athletes in creating specialized training strategies and techniques.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

The studies involving humans were approved by Comité de Ética de la Universidad de León. The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study. Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article.

DS-I: Conceptualization, Data curation, Funding acquisition, Investigation, Visualization, Writing – original draft, Writing – review & editing. CA: Supervision, Writing – original draft, Writing – review & editing. AG-F: Formal analysis, Writing – original draft, Writing – review & editing. JV-V: Conceptualization, Data curation, Funding acquisition, Methodology, Writing – original draft, Writing – review & editing. JuR-M: Writing – original draft, Writing – review & editing. JoR-M: Methodology, Project administration, Resources, Writing – original draft, Writing – review & editing.