Warm-up of the Inspiratory Musculature and Its Impact on Physiological Parameters and Swimming Performance: Exploration of Intensities Based on Maximal Inspiratory Pressure
Warm-up of the Inspiratory Musculature and Its Impact on Physiological Parameters and Swimming Performance: Exploration of Intensities Based on Maximal Inspiratory Pressure
Objective To evaluate the acute effect of four inspiratory warm-up intensities (15%, 40%, 60%, and 80% of maximal inspiratory pressure [MIP]) on 100 m freestyle performance, and to analyze their impact on heart rate, blood lactate concentration, perceived exertion, and dyspnea in trained swimmers.
Methods A randomized, crossover, double-blind experimental study was conducted. Participants were swimmers aged ≥18 years, with no respiratory or musculoskeletal pathology.
Each participant completed, in sessions separated by at least three days, an inspiratory muscle warm-up consisting of 30 breaths against resistive loads set at 15%, 40%, 60%, and 80% of their MIP, previously determined using standardized procedures.
Following each intervention, participants performed a maximal 100 m freestyle test. The following variables were recorded:
Swimming time Heart rate (during and post-exercise) Post-exercise capillary blood lactate concentration Rating of perceived exertion (Borg scale) Dyspnea (Dyspnea-12)
Conclusions This study will help identify the optimal inspiratory warm-up intensity to enhance swimming performance.
Inspiratory warm-up
An intervention performed prior to exercise consisting of breathing against resistance to activate the inspiratory muscles (mainly the diaphragm and accessory respiratory muscles) with the aim of enhancing their performance during subsequent effort.
Maximal Inspiratory Pressure (MIP)
The maximum pressure that an individual can generate during a forceful inspiration against an occluded airway. It is an indicator of inspiratory muscle strength and is used to prescribe training intensity.
Relative intensities (15%, 40%, 60%, 80% of MIP)
Percentages of MIP representing different levels of respiratory workload. They allow graded inspiratory resistance to investigate dose-response effects on performance.
Inspiratory Muscle Training (IMT)
A specific training method targeting the inspiratory muscles through controlled resistive breathing loads, aimed at improving strength, endurance, and ventilatory efficiency.
Crossover design
An experimental design in which each participant completes all experimental conditions, acting as their own control, thereby reducing inter-subject variability.
Double-blind design
A methodological approach in which neither participants nor evaluators are aware of the assigned condition, minimizing bias in performance and outcome assessment.
Swimming performance
A functional outcome measured primarily through time to complete a fixed distance, in this case 100 meters freestyle.
Cardiovascular response
The physiological response of the cardiovascular system to exercise, typically assessed through heart rate and post-exercise recovery dynamics.
Blood lactate concentration
A marker of metabolic stress during high-intensity exercise, reflecting the contribution of anaerobic glycolysis to energy production.
Perceived exertion
A subjective assessment of exercise intensity, commonly measured using standardized scales such as the Borg scale.
Respiratory discomfort (dyspnea)
A subjective sensation of breathing difficulty associated with exertion, reflecting ventilatory demand and exercise tolerance.
Inclusion criteria:
Exclusion criteria: