###### Abstract  
The aim of this study was to evaluate whether and how anaerobic fatigue induced by sport-specific exercise affects the postural control of highly-trained adolescent road cyclists. Twenty-three male athletes, aged 15-18 years, were included in the study. Postural control was assessed using the pedobarographic platform (bipedal upright stance, sequentially, with eyes open (EO) and closed (EC) for 60 s each, with a 30 s interval), before and 3 min after a 30 s all-out effort performed on the ergometer. The results showed significant increases in the 95%-confidence ellipse area (\(p\)-value 0.000 and 0.001 for EO and EC, respectively), as well as centre-of-pressure (CoP) range displacement in the anteroposterior (\(p\)-value 0.000 for both EO and EC) and mediolateral (\(p\)-value 0.011 and 0.001 for EO and EC, respectively) planes. In addition, a significant decrease in CoP mean sway frequency was observed (\(p\)-value 0.000 and 0.001 for EO and EC, respectively), but no changes were noted in CoP mean velocity (\(p\)-value 0.316 and 0.670 for EO and EC, respectively). In our study, it has been indicated that anaerobic fatigue induced by sport-specific exercise deteriorates postural control in adolescent cyclists. Moreover, cycling training may affect the quality of postural corrective reactions occurring in response to anaerobic fatigue. postural control; body sway; anaerobic fatigue; cyclists; sport-specific exercise +
Footnote †: journal: Medical  
The human body in the upright bipedal standing position is constantly swaying due to the inability of the neuromuscular system to maintain constant muscular tension [8] as well as the presence of physiological destabilising factors such as body liquid movements, heart work, and respiratory muscular contraction [9; 10]. Despite this, the human body is able to maintain a vertical projection of the centre of gravity within the base of support due to the operation of the postural control system. The quality of postural control may be quantified by registering the trajectory of the centre of pressure (CoP) using force platforms, which track the point of application regarding ground reaction forces resultant under the feet present during upright standing [11]. The resulting signal, called the stabilogram, provides various parameters describing postural control quality such as positional parameters (e.g., 95%-confidence ellipse area [EA], distance between extreme points of the stabilogram (range) in anteroposterior [AP\({}_{\text{R}}\)] and mediolateral [ML\({}_{\text{R}}\)] planes, as well as \(\text{AP}_{\text{R}}/\text{ML}_{\text{R}}\) ratio), dynamic parameters (e.g., CoP mean velocity [MV] calculated as path length divided by time of measurement), and frequency parameters (e.g., CoP mean frequency [MV] defined as the rotational frequency, considering the total CoP length as a trajectory around a circle with a radius equal to the mean distance) [11]. Generally, exercises that solicit a large part of body musculature (general exercise)--for instance, cycling--cause the aggravation of postural sway due to increased cardiac and breathing rhythm as well as intensified body liquid flow [12]. Moreover, general exercise generates fatigue which affects postural control by decreasing the quality of input sensory information and its integration, as well as output motor command efficiency. The crucial exercise parameters influencing the size of postural sway aggravation and postural control deterioration are intensity and duration. A large acid-base imbalance due to the dissociation of lactic acid produced into lactate and hydrogen is typical for high-intensity, short-term exercises. In contrast, low-intensity, long-term exercise may cause elevated body temperature, dehydration, muscle damage, and/or the depletion of glycogen storage [13]. In addition, the size of postural control deterioration may depend on exercise type, intensity of proprioceptive stimulation, forms of muscle contraction, and the activation of muscle fibres [14].