Match Demands and Perceived Exertion of Cerebral Palsy Soccer National Team Players

Abstract

Background:

The aims of this study were to analyze match demands and perceptual responses of cerebral palsy soccer national team players. Specifically, to identify whether variations in match demands exist between playing positions and between halves.

Hypothesis:

Differences between playing positions exist and match demands differ from first to second half.

Study Design:

Cohort study.

Level of Evidence:

Level 3.

Methods:

An observational, longitudinal study was conducted over the 2022-2023 season. Electronic performance and tracking systems collected physical output, whereas perceptual responses were collected through ratings of perceived exertion postmatch.

Results:

Playing position significantly affected all variables (F_(4,66) = 4.05-73.31; P < .001; η_p² = 0.20-0.82). Midfielders had the greatest average physical output in all variables, except for high-intensity accelerations per minute (forwards = ~0.19 count/min) and maximum velocity (full-backs = ~28.87 km/h). Match half had no significant effect on any variable (F_(4,66) = 0.00-1.38; P > .05; η_p² = 0.00-0.02), except for distance per minute, which was usually greater in the first half than second half (F_(1,66) = 7.15; P = .01; η_p² = 0.10). Regarding perceptual response, playing position had a significant effect, with goalkeepers having significantly lower ratings of perceived exertion compared with the other positions (P < .05).

Conclusion:

Playing position significantly affected all variables, with goalkeepers showing the lowest demands, followed by central defenders. Midfielders had the highest physical output across most variables, except for high-intensity accelerations per minute (forwards) and maximum velocity (full-backs). Match half had no significant effect on any variable, except for distance per minute.

Clinical Relevance:

Understanding match demands and positional differences in cerebral palsy soccer helps coaches plan tailored training sessions and drills to meet specific physical outputs. This knowledge supports training periodization, optimal player performance, and recovery. Insights into physical challenges for each position assist in scouting and adjusting training intensity.

Keywords

athlete football GPS monitoring paralympic;soccer

Cerebral palsy (CP) is an upper motor neuron disorder, consisting of several conditions of posture and motor impairment resulting from complications in the developing brain.² CP is known as the most common pediatric neurological disorder and causes a wide variety of physical impairments and symptoms.²⁰ It typically occurs during the birth process or in the early childhood years.¹² CP soccer is a parasport for ambulant athletes with eligible impairments including varying levels of hypertonia, athetosis, or ataxia, which are common health conditions resulting from CP, traumatic brain injury, or stroke.¹⁵

These impairments have been shown to negatively impact physical and athletic performance.²⁷ People with CP often experience a range of physical symptoms, including varying degrees of muscle weakness and contraction, impaired balance, muscle spasticity, and poor coordination.³² These can result in reduced agility, slower reaction times, and a decreased capacity to sustain high-intensity activities, all of which can significantly influence their athletic potential.³² In addition to these motor disturbances, people with CP often experience disruptions in sensation, cognition, perception, communication, and behavior.¹² As mentioned, the degree of impairment varies. CP can either be unilateral (affecting one limb or one side of the body), or bilateral (affecting both sides of the body), so any number of limbs can be affected.¹² Whereas monoplegia affects only one limb (typically the lower limb), hemiplegia impacts one side of the body, with the upper limb usually experiencing greater impairment.¹² Diplegia affects all limbs of the body, with the lower limbs likely being more impaired.¹² The common pattern in triplegia is unilateral upper limb impairment and bilateral lower limb impairment.¹² Finally, quadriplegia affects all 4 limbs and the trunk.¹² Previous studies have investigated how CP specifically affects soccer performance. For example, when comparing results from the Yo-Yo Intermittent Recovery Level 1 Test between soccer for people with CP and able-bodied soccer players, it was observed that the distance covered by the players with CP on average was 43% to 50% below the mean distance of able-bodied players.¹⁸ Results from other studies have shown that soccer players with CP cover less distance at high-intensity running and sprinting, performed fewer numbers of moderate and high-intensity accelerations and decelerations, and had a lower player load in official matches compared with conventional soccer players.³⁹

CP soccer has several differences in relation to conventional soccer. The game duration is 60 minutes (two 30-minute halves), is played as 7 aside with no offside rules, and includes a smaller field and goals.³⁶ Like all Parasport athletes, soccer players with CP are classified according to their severity of impairments in an effort to control the impact of such impairments on competitive outcomes.¹⁶ The current classification system for soccer players with CP includes 3 impairment categories consisting of bilateral spasticity, coordination issues produced by ataxia or dyskinesia, and unilateral spasticity.²⁹ The severity of the impairment is assessed in relation to physical and soccer-related tasks, with the International Federation of CP Football evaluating and classifying players into 3 classes based on these impairments: FT1 (most impaired), FT2 (moderate), and FT3 (least impaired).¹³ Previous research into the physical profiles and external loads of soccer players with CP have found significant differences between classes.¹¹ Other studies have found a direct correlation between the physical performance of a soccer player with CP (via physical performance tests such as counter-movement jump, sprint tests, and dribbling tests) and their external load during matches.²⁸ Those athletes that performed better in these physical tests, due to having less impairment, were found to cover more distance at higher intensities and perform more accelerations and decelerations than their more impaired counterparts.²⁸

However, they all play the same game and may be exposed to different physical demands. Research into CP soccer, and specifically match demands, has been increasing but, to our knowledge, research on the positional differences in external load and reported perceptual responses of players with CP is scarce. Thus, the aim of this study was to analyze the positional match demands and perceptual responses of CP soccer national team players. Specifically, the study aimed to identify differences in match demands between different playing positions and between the first and second halves of matches.

Methods

Experimental Approach to the Problem

An observational, longitudinal study was conducted over the course of the 2022-2023 season. This consisted of 8 official games: 3 international friendlies and 5 games at the International Federation of Cerebral Palsy Football World Cup. All matches were played at the highest international CP soccer level against other national teams in 3 separate competitions. The sample included 4 wins, 2 draws, and 2 losses, representing a diverse range of match outcomes. Although all matches were played against top-level opposition, the varying match results might reflect differences in team strategies, game contexts, or physical demands across the sample. Although the number of players and field size is reduced, which makes the interchanging of positions more frequent, all players remained in their same starting position throughout each game. The team formation used was a 1-3-2-1: 1 goalkeeper, 3 defenders (1 centerback and 2 fullbacks), 2 midfielders, and 1 forward. Electronic performance and tracking systems were used to collect the physical output while perceptual responses were collected through rating of perceived exertion (RPE) postmatch. This study was approved by the Institutional Review Board at the University of Tampa (code, 23-111).

Participants

A total of 14 CP soccer national team players participated voluntarily in this study (age, 26.22 ± 4.89 years old; height, 1.74 ± 0.10 m; weight, 76.69 ± 9.06 kg). Since the aim of this study was to explore the match demands of players with CP, players were selected based on their availability and participation in full matches. Match data from substitutes were excluded from this study so as not to dilute the overall match demands of each playing position. To evaluate the adequacy of the sample size, the study achieved sufficient statistical power (>0.80). This led to a total of 38 match observations from 9 players who participated in full games, all other substitute data were omitted. The total time analyzed across all matches was 564.38 minutes, with a total average of 70.54 minutes per match (ie, extra time was included in the analysis). Match observations were collected from multiple playing positions (goalkeepers [GK], n = 10; central defenders [CD], n = 10; fullbacks [FB], n = 24; midfielders [MF], n = 24; forwards [FW], n = 8). As mentioned, athletes are classified into 1 of 3 classes based on the severity of impairments, which can include varying levels of hypertonia, ataxia, or athetosis. To ensure fair competition, at least 1 FT1 player (most severe impairment) must be on the field at all times, and only 1 FT3 player (least severe impairment) is permitted on the field at all times.¹⁵ All players in this study were classified as FT2, except 1 FT1 (CD) and another FT3 (MF). None of the athletes were wearing assistive devices such as braces or prosthetics, which could affect onfield performance.

Procedures

Global-Positioning-System-derived data were collected at 10 Hz using Statsports Apex Pro Series (STATSports). These units are used widely in team sports, especially soccer, and have shown great levels of accuracy in a variety of sport specific metrics.³ The units were set up and calibrated per the manufacturer’s instructions: units were separated by at least 1 meter and turned on 15 minutes before player collection, after which they were placed on the upper back in the pouch of a specific vest. Once each match had concluded, the units were collected, and data were downloaded to the STATSports software.

Specifically, the following variables were analyzed: distance covered (meters), m/min, high speed running distance (HSRD, >19.8 km/h), HSRD/min, high intensity accelerations (ACC_HIGH, >4 m/s² for minimum duration of 0.5 s), ACC_HIGH/min, high intensity decelerations (DEC_HIGH, < –4 m/s² for minimum duration of 0.5 seconds), DEC_HIGH/min, high metabolic load distance (HMLD, >25.5 W/kg), HMLD/min, and maximum velocity (Vmax).^4,21,30,39 The speed, acceleration, and metabolic load thresholds are similar to that reported by previous studies.^4,21,30,39 In addition, RPE was collected approximately 30 minutes after each match using the Borg CR-10 scale.⁹

Statistical Analysis

First, descriptive statistics were obtained to analyze the match demands and perceived exertion as means and standard deviations of CP soccer national team players. The Kolmogorov-Smirnov test was used to confirm the normality of the dataset. Also, Levene’s test was used for the assessment of equality of variances. Data were then analyzed using a univariate analysis of variance to investigate the effect of contextual factors such as playing position or match half on match demands. Also, the pairwise comparisons to identify differences in total match demands between different playing positions and between the first and second halves of matches were performed using the Bonferroni method. The effect size (ES) for all variables was analyzed using the partial eta squared (η_p²). The η_p² values were interpreted qualitatively using the following thresholds: small (ES, 0.01-0.059), medium (ES, 0.06-0.14), and large (ES, >0.14).⁷ Alpha was set at P < .05. Data analysis was performed using SPSS (IBM, SPSS Statistics, Version 29.0.1).

Results

Table 1 shows the match demands of national team players with CP. Playing position had a significant effect on all variables (F_(4,66) = 4.05-73.31; P < .001; η_p² = 0.20-0.82; large ES). Given the activity profile of GK, this was the position with the lowest physical demands (P < .05). Apart from GK, CD was the playing position which showed the lowest average physical output in most of the variables: HSRD, HSRD/min, HMLD, HMLD/min, ACC_HIGH, ACC_HIGH/min, distance per minute, and Vmax. However, MF was the position with the greatest average physical output in all variables, except for ACC_HIGH/min (FW = ~0.19 count/min) and Vmax (FB = ~28.87 km/h). Specifically, MF covered significantly: (1) greater total distance than CD (~376.39 m; P = .04) and FB (~439.91 m; P < .001); (2) greater distance per minute than CD (~13.98 m; P = .004) and FB (~11.91 m; P = .001); (3) greater HMLD than CD (~219.65 m; P < .001) and FB (~162.41 m; P < .001); (4) greater HMLD/min than CD (~6.75 m; P < .001) and FB (~4.55 m; P = .002); (f) greater HSRD than CD (~106.93 m; P = .005); (f) greater HSRD/min than CD (~3.08 m; P = .005).

Table 1.

Match demands of national team players with CP by playing position and match half

Variable	Period	GK (Mean ± SD)	CD (Mean ± SD)	FB (Mean ± SD)	MF (Mean ± SD)	FW (Mean ± SD)	Effect of position	Effect of match half	Interaction position × half
Distance, m	First half	1627.30 ± 182.11	3429.44 ± 130.99	3245.35 ± 296.92	3732.10 ± 206.25	3230.16 ± 769.22	F (4,66) = 73.31 P < .001 η_p²= 0.82	F (1,66) = 0.10 P = .75 η_p²= 0.00	F (4,66) = 0.65 P = .63 η_p²= 0.04
	Second half	1515.60 ± 246.63	3284.29 ± 490.25	3341.35 ± 352.70	3734.43 ± 335.62	3527.70 ± 378.53
	Total	3142.90 ± 383.27^b,c,d,e	6713.72 ± 570.65^a,d	6586.70 ± 617.17^a,d	7466.52 ± 482.81^a,b,c	6757.86 ± 592.98^a
Distance per time, m/min	First half	48.84 ± 4.71	97.96 ± 6.65	98.07 ± 9.50	111.04 ± 7.49	99.08 ± 29.10	F (4,66) = 68.97P < .001η_p²= 0.81	F (1,66) = 7.15P = .01η_p²= 0.10	F (4,66) = 0.25P = .91η_p²= 0.02
	Second half	41.85 ± 5.89	87.59 ± 12.27	91.64 ± 8.28	102.49 ± 6.86	97.31 ± 7.09
	Total	45.35 ± 3.84^b,c,d,e	92.78 ± 7.07^a,d	94.85 ± 8.40^a,d	106.76 ± 5.55^a,b,c	98.20 ± 12.65^a
HSRD, m	First half	2.29 ± 5.13	74.01 ± 17.23	139.15 ± 74.43	147.13 ± 87.03	118.82 ± 59.35	F (4,66) = 10.90P < .001η_p² = 0.39	F (4,66) = 0.19P = .66η_p² = 0.00	F (4,66) = 0.61P = .65η_p² = 0.03
	Second half	3.51 ± 7.20	53.64 ± 42.02	177.32 ± 87.32	194.39 ± 118.11	96.05 ± 21.82
	Total	5.80 ± 12.31^c,d	127.65 ± 40.21^c,d	316.47 ± 142.12^a,b	341.52 ± 192.91^a,b	214.87 ± 73.29
HSRD per minute, m/min	First half	0.07 ± 0.17	2.14 ± 0.63	4.17 ± 2.22	4.37 ± 2.53	3.66 ± 2.03	F (4,66) = 10.72P < .001η_p² = 0.39	F (4,66) = 0.00P = .99η_p² = 0.00	F (4,66) = 0.48P = .75η_p² = 0.03
	Second half	0.11 ± 0.22	1.43 ± 1.12	4.87 ± 2.43	5.36 ± 3.33	2.69 ± 0.82
	Total	0.09 ± 0.19^c,d	1.75 ± 0.51^c,d	4.54 ± 2.09^a,b	4.88 ± 2.78^a,b	3.15 ± 1.30
ACC _HIGH, count	First half	3.40 ± 2.07	3.40 ± 2.41	4.83 ± 2.37	6.42 ± 4.32	6.25 ± 4.79	F (4,66) = 4.66P = .006η_p² = 0.20	F (1,66) = 0.29P = .87η_p² = 0.00	F (4,66) = 0.26P = .90η_p² = 0.02
	Second half	2.20 ± 1.48	3.20 ± 0.84	4.00 ± 2.80	7.17 ± 4.26	7.00 ± 5.29
	Total	5.60 ± 3.13^d	6.60 ± 2.30	8.83 ± 4.00	13.58 ± 6.78^a	13.25 ± 9.00
ACC _HIGH, count/min	First half	0.10 ± 0.05	0.09 ± 0.06	0.15 ± 0.07	0.19 ± 0.11	8.00 ± 8.25	F (4,66) = 4.05P = .01η_p² = 0.20	F (1,66) = 0.31P = .58η_p² = 0.01	F (4,66) = 0.24P = .92η_p² = 0.01
	Second half	0.06 ± 0.04	0.09 ± 0.02	0.11 ± 0.08	0.20 ± 0.13	6.00 ± 5.89
	Total	0.08 ± 0.04^d	0.09 ± 0.03	0.13 ± 0.06	0.19 ± 0.10^a	0.19 ± 0.13
DEC _HIGH, count	First half	1.60 ± 1.52	6.00 ± 2.35	8.25 ± 3.62	9.33 ± 3.87	8.00 ± 8.25	F (4,66) = 5.62P < .001η_p² = 0.25	F (1,66) = 0.29P = .59η_p² = 0.00	F (4,66) = 0.49P = .74η_p² = 0.03
	Second half	3.00 ± 1.87	9.00 ± 3.32	7.92 ± 4.66	10.17 ± 4.57	6.00 ± 5.89
	Total	4.60 ± 1.34^c,d	15.00 ± 4.53	16.17 ± 6.37^a	19.50 ± 6.67^a	14.00 ± 13.12
DEC_HIGH, count/min	First half	0.05 ± 0.04	0.17 ± 0.07	0.25 ± 0.12	0.28 ± 0.12	0.25 ± 0.26	F (4,66) = 5.44P < .001η_p² = 0.25	F (1,66) = 0.02P = .90η_p² = 0.00	F (4,66) = 0.59P = .67η_p² = 0.03
	Second half	0.08 ± 0.05	0.24 ± 0.09	0.22 ± 0.13	0.28 ± 0.12	0.16 ± 0.15
	Total	0.07 ± 0.02^c,d	0.21 ± 0.06	0.23 ± 0.09^a	0.28 ± 0.10^a	0.20 ± 0.19
HMLD, m	First half	44.39 ± 14.24	488.48 ± 52.67	506.73 ± 127.34	676.02 ± 109.88	568.50 ± 242.21	F (4,66) = 42.91P < .001η_p² = 0.72	F (1,66) = 0.00P = .96η_p² = 0.00	F (4,66) = 0.21P = .93η_p² = 0.01
	Second half	45.41 ± 16.79	446.64 ± 110.00	542.88 ± 169.08	698.42 ± 133.21	542.83 ± 162.05
	Total	89.80 ± 22.12^b,c,d,e	935.12 ± 159.45^a,d	1049.61 ± 280.96^a,d	1374.44 ± 213.64^a,b,c	1111.33 ± 354.13^a
HMLD, m/min	First half	1.33 ± 0.42	13.92 ± 1.28	15.34 ± 4.15	20.14 ± 3.46	17.43 ± 8.20	F (4,66) = 39.66P < .001η_p² = 0.71	F (1,66) = 1.38P = .24η_p² = 0.02	F (4,66) = 0.17P = .96η_p² = 0.01
	Second half	1.21 ± 0.47	11.91 ± 2.85	14.89 ± 4.68	19.20 ± 3.75	15.03 ± 4.45
	Total	1.30 ± 0.35^b,c,d,e	12.86 ± 1.87^a,d	15.10 ± 4.20^a,d	19.64 ± 3.18^a,b,c	16.13 ± 5.54^a
Vmax, km/h	First half	17.30 ± 3.34	26.48 ± 2.89	27.81 ± 2.68	27.13 ± 2.89	27.08 ± 1.12	F (4,66) = 24.49P < .001η_p² = 0.60	F (1,66) = 0.00P = .99η_p² = 0.00	F (4,66) = 0.90P = .47η_p² = 0.05
	Second half	19.81 ± 3.76	25.26 ± 2.54	28.17 ± 1.74	26.80 ± 2.63	25.70 ± 1.74
	Total	19.83 ± 3.75^b,c,d,e	27.07 ± 2.49^a	28.87 ± 2.12^a	27.76 ± 2.48^a	27.21 ± 1.22^a

Significant differences (P < 0.05) in full-match demands compared with GK^a, CD^b, FB^c; MF^d, FW^e. HSRD, high-speed running distance; ACC_HIGH, high intensity accelerations; DEC_HIGH, high intensity decelerations; HMLD, high metabolic load distance; Vmax, maximum velocity; GK, goalkeeper; CD, central defender; FB, fullback; MF, midfielder; FW, forward.

However, the results showed that match half had no significant effect on any variable (F_(4,66) = 0.00-1.38; P > .05; η_p² = 0.00-0.02; small ES), except for distance per minute, in which the meters per minute were usually greater in the first half than second half (F_(1,66) = 7.15; P = .01; η_p² = 0.10). In addition, the interaction between playing position and match half was not significant (F_(4,66) = 0.17-0.65; P > .05; η_p² = 0.01-0.05; small ES).

When it comes to perceptual response after the match, playing position had a significant effect on RPE (F_(4,66) = 10.11; P < .001; η_p² = 0.38; large effect size) (Figure 1). However, GK was the only position that had significant lower RPE compared with the rest of playing positions (CD, –1.8 + 0.4 arbitrary units [a.u.]; FB: –1.7 + 0.33 a.u.; MF: –2.00 + 0.33 a.u.; FW: –2.00 + 0.42 a.u.).

Discussion

The purpose of this study was to analyze the match demands and perceptual responses of CP soccer national team players. One of the main findings was that playing position had a significant effect on all variables, with GK being the position with the lowest demands given its activity profile, followed by CD as the playing position that showed the lowest average physical output in most of the variables. MF was the position with the greatest average physical output in all variables, except for ACC_HIGH/min (FW = ~0.19 count/min) and Vmax (FB = ~28.87 km/h). Another main finding was that match half had no significant effect on any variable, except for distance per minute, in which the meters per minute were usually greater in the first half than in the second half.

These findings are in line with previous research in the 11-a-side game. In able-bodied 11-a-side soccer, GK have been found to cover less than half the total distance and less than one-tenth the sprinting distance of outfield players.^5,35 This makes sense due to the distinctive role and often static position that GK play on the field in relation to outfield players.³⁵ In terms of outfield players, CD were also found to cover the lowest amount of total distance. Of all playing positions, they covered the highest distance at the lowest intensity (walking/jogging) and the lowest distance at all higher intensities.³⁴ On the other hand, MF were found to cover the highest total distance and the highest distances at high-speed running and sprinting, which is also in line with the findings from this study.³⁴ From a practical perspective, this difference in physical output suggests the importance of an individualized approach to training load management, nutritional strategies, and other recovery modalities for players with CP. However, differences between classes should be considered. Due to their lower physical impairments, FT3 players have been found to cover greater distances at high speeds and record a higher number of impacts throughout a match. However, FT2 players have shown in some instances to have greater physical demands than FT3 players. FT1 players have demonstrated the lowest demands due to the increased severity of impairments.¹¹

Regarding the analysis of differences between match halves, distance per minute (also known as average speed) has been reported previously in research into conventional soccer, as players have been shown to cover lower distance in the second half, thereby reducing meters per minute.³⁸ It has been hypothesized that this reduction in intensity may be a self-pacing strategy to conserve high intensity running capacity for the latter stages of the second half, to avoid fatigue induced injury, or may be the result of fatigue itself.^8,34,37 However, our finding that match half had no significant effect on other metrics of physical output is contrary to some previous studies in conventional soccer. Previous research has found that the total distance covered is greater in the first half than in the second half for all playing positions.³¹ At some positions in this study (FB, MF, FW), although not significant, total distance actually increased in the second half. Similarly, research has found reductions in high-speed running in the second half compared with the first.³¹ Again, our findings showed no significant differences here, and FB and MF showed an increase in high-speed running distance in the second half, although this increase was not significant. This could be due to several factors. As mentioned earlier, these increases in high-intensity running may be a result of self-pacing strategies that begin in the first half and early stages of the second half to conserve adequate energy for the later stages of the game, especially for the FB and MF positions, which require more high-intensity running.³⁴ This may also be a result of the outcome of the game. If the match is closely contested, it could require more high-intensity actions to either win the game or conserve the lead. It should be noted also that the length of the game is shorter and the field dimensions are smaller in CP soccer versus 11-a-side soccer, so comparisons between the 2 must be made with caution. For a better understanding of these changes between halves, it would be interesting to look further into the changes in physical performance throughout various intervals in a CP soccer match. For instance, a recent study with CP players observed significant differences across 10-minute periods (0-10, 10-20, 20-30, 30-40, 40-50, and 50-60 minutes).¹¹ In this regard, recent studies into professional 11-a-side soccer have examined the variation in match demands over 15-minute periods.^19,22,24 One such study found that the highest levels of performance were usually in the first half, with distance and high-intensity accelerations/decelerations being highest in the first 15 minutes, and number of sprints, sprint distance, and HMLD being highest in the 30- to 45-minute period.²⁴ On the other hand, the lowest mean physical performance was found in the later stages of the second half.²⁴ Future research should examine whether similar trends are observed in CP soccer and whether there are any positional differences through these periods. As the length of the CP game is shorter than 11-a-side, the game could be split into 6 10-minute periods and the same physical metrics could be assessed. Another area worth exploring further is the correlation between the microcycle periodization and its effect on matchday performance. Recent studies have examined this relationship and have found that shorter duration microcycles (5-day, 6-day, or 7-day) showed subsequent declines in physical performance as compared with longer microcycles (8-day or 9-day).²³ CP soccer has a unique structure, as tournaments will typically involve consecutive matches with little or no rest in between, making the periodization for microcycles challenging. An understanding of the microcycle periodization and how consecutive matches affect physical performance was beyond the scope of this study, but further analysis should examine this to determine the best possible strategies for training loads and management of multiple games during a microcycle.

Finally, it is important to mention that there has been limited research into the perceptual responses in relation to playing position in CP soccer. Results from this study found that playing position had a significant effect on RPE, but GK was the only position with a significant lower RPE compared with other playing positions. Previous research into perceptual responses in 11-a-side player positions has found that GK reported significantly lower RPE scores as compared with all other positions.¹⁷ This is not surprising, as the role GKs play is different than the open field positions, and involves a unique physical profile comprising of short, explosive actions such as accelerations/decelerations, jumps, and dives.¹⁷ Previous research on CP soccer players reported RPE values of ~5.5 for defenders, ~6.3 for midfielders, and ~6.6 for attackers, though no significant differences were found in overall and pairwise comparisons for RPE across classes and playing positions.¹³ In addition, another study highlighted the importance of interpreting the physiological responses of CP soccer players as they are of fundamental importance for performance.¹⁰ The study examined heart rate variability and daily session-RPE of CP soccer players, reported values between 400 and 800 a.u., and found that a week of training with mean session RPE of ~600 a.u. led to changes in heart rate variability (eg, standard deviation of NN intervals, root mean square of successive RR interval differences, low frequency, and high frequency.¹⁰

A few limitations have been identified in this study. Although this study focused on positional match demands and perceptual responses, it is important to consider other contextual factors (the level of the opposing team, team ranking, length of the microcycle, etc), which may influence the results.^1,6,14,25,26 Future research should aim to incorporate these contextual variables to provide a more comprehensive understanding of CP soccer match demands. Moreover, this study is limited by the sample size and focus on a single CP national team, which restricts the generalizability of the findings. The exclusion of substitutes and reliance on full-match observations further narrowed the scope of analysis. For a more inclusive understanding of positional match demands, a larger sample size including players from different nationalities is warranted. Players from other nationalities may have different upbringings, training regiments, coaching, technical abilities, tactical styles, etc, all of which can have a significant impact on the specific match demands of playing positions. Also, the use of default speed and acceleration thresholds from able-bodied 11-a-side soccer research, rather than CP-specific thresholds might limit the accuracy of the analysis. In addition, since this study included all classes (FT1, FT2, and FT3), variabilities in impairments likely influenced positional outputs. As previous research in CP soccer has shown, differences in physical output between classes can be explained by the varying levels of impairment.¹³ Based on limited studies, future research could focus on the difference in match demands between classes playing in the same position. This would allow for a more comprehensive understanding of how certain levels of impairments affect the demands on players of a specific class at a specific position. Further research should look to identify average outputs in each of the speed zones to determine appropriate thresholds for use with players with CP if not using individual thresholds. Research could also determine average thresholds for each of the 3 classes, which would allow for more accurate analysis of match demands for each level of impairment.

Practical Applications

This study provides new insights into the match demands and perceptual responses of CP soccer national team players, highlighting significant positional differences in physical output and perceived exertion. For coaches and sport scientists, knowledge of the physical output that players will be subjected to in a game can help them plan sessions and tailor drills that will achieve the desired demands for that particular training day. For example, if an MF may cover ~106 m/min in a match, training drills aimed at replicating the competitive demands of CP soccer should be above this threshold. Periodization of training at the macro and microcycles of the season is commonplace in the modern game, and consideration of the physical demands is paramount. The base of this knowledge stems from the match demands. From here, coaches and sport science professionals can work together to plan and monitor training so that players are not overtraining or undertraining and are in the best possible condition to perform on matchday.

In addition, understanding the different physical challenges faced at each position can also help coaches plan specific drills and adjust the intensity to ensure that each positional player is getting the correct amount of training. Coaches can also use the physical metrics as a guide for scouting new players. A full comprehension of the fitness levels required for each position can help measure new players in comparison with those already on the team.

The lack of significant differences between match halves is also worth noting. As mentioned, this may be due in part to the shorter duration of match halves and smaller field dimensions in CP soccer as compared with 11-a-side soccer. The nature of 7-a-side soccer may make it harder to use self-pacing strategies that are commonly seen in conventional soccer due to the smaller field size and constant involvement. Practitioners may also use this information to their advantage. Pacing strategies in CP soccer are an underexplored topic, but perhaps self-pacing strategies that are commonly seen in 11-a-side soccer are not necessary in CP soccer. However, a previous study on track sprinters with CP demonstrated evidence that conservative pacing strategies served as an underlying factor in exercise performance and fatigue patterns in these athletes.³³ Further investigations could explore how fatigue plays a role in CP soccer, as there have been some interesting findings in the literature. One such study looked at the differences in match load after playing 2 consecutive matches and found that match load variables were not different between the 2 games, which is a stark contrast to conventional soccer.²⁸ A greater understanding of how fatigue affects soccer players with CP will help practitioners in many avenues, including tactics, player management, recovery, etc.

Finally, although this study did not analyze nutritional demands, understanding match demands could indirectly guide nutrition planning. Knowledge of the physical output required for each position may help inform on the energy requirements of CP soccer players and nutritional strategies to optimize performance and recovery.

Footnotes

The authors report no potential conflicts of interest in the development and publication of this article.

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