. 2022 Feb 24;13:796097. doi: 10.3389/fphys.2022.796097

TABLE 3.

Research gaps identified in the literature and suggestions for future studies.

Gaps and limitations revealed in the literature	Suggestions for future studies
There is a lack of studies investigating the relationship between core stability or core strength and functional movement and/or athletic performance. There is still inconsistent definition of core stability and core strength in spite of an increased number of studies in this field of research. The research in this field has been conducted mainly in shooting, biathlon, archery, gymnastics, and team sports. More research has been carried out in team than individual sports. Small sample sizes occur in most studies, which could reduce its power and increase the margin of error. There are only few studies conducted on competitive athletes of a high performance level. The analysis of the literature in this scoping review related to the role of core stability in functional movement and/or athlete performance revealed that nine studies (69%) were conducted with regularly competing high school or university athletes or athletes from lower competitions (Stanton et al., 2004; Abt et al., 2007; Chaudhari et al., 2011; Saeterbakken et al., 2011; Ozmen, 2016; Anand et al., 2017; Kuhn et al., 2019; Felion and DeBeliso, 2020; de Bruin et al., 2021), three studies (23%) with young elite athletes (Nesser et al., 2008; Nesser and Lee, 2009; Vitale et al., 2018), and one study (8%) with very young athletes (Sannicandro and Cofano, 2017). Regarding the age of participants, eight studies (62%) included adult athletes (Abt et al., 2007; Nesser et al., 2008; Nesser and Lee, 2009; Chaudhari et al., 2011; Ozmen, 2016; Anand et al., 2017; Kuhn et al., 2019; de Bruin et al., 2021) and five studies involved young athletes (Stanton et al., 2004; Saeterbakken et al., 2011; Sannicandro and Cofano, 2017; Vitale et al., 2018; Felion and DeBeliso, 2020). There is a lesser number of research studies conducted on female than male participants. Regarding gender, the analysis of the literature related to the role of core stability in functional movement and/or athlete performance revealed that eight studies (62%) included male athletes (Stanton et al., 2004; Abt et al., 2007; Nesser et al., 2008; Chaudhari et al., 2011; Ozmen, 2016; Anand et al., 2017; Vitale et al., 2018; Felion and DeBeliso, 2020), four studies (31%) female athletes (Nesser and Lee, 2009; Saeterbakken et al., 2011; Kuhn et al., 2019; de Bruin et al., 2021), and one study (7%) both girls and boys (Sannicandro and Cofano, 2017). The control group is rarely included. Non-sporting population cannot be included in most of the studies because of the athletic performance tests used. There is a missing information on the level of athlete performance. General physical fitness tests rather than sport-specific tests are used. Variables analyzed are not precisely described. Experiments are conducted in different training periods (pre-season, in-season, post-season) what limits a comparison of findings. The average duration of training programs is from 4 to 8 weeks while the training sessions vary from 25 to 30 min, in some cases even from 60 to 75 min, which very often combine balance, strength and core muscle exercises. There is insufficient analysis of neuromuscular mechanisms underlying significant associations of postural and core stability with functional movement and/or athlete performance. Balance, strength, plyometric or endurance exercises are usually associated with training induced improvements of postural and core stability but not with athlete performance.	In comparison with balance research, more attention should be paid to investigations related to the role of core stability and core strength in functional movement and/or athletic performance. The authors should use uniform terminology of core stability and core strength based on their characteristics, similarly as it is in the case of balance research. As core stability and strength represent an integral part of athlete performance in sports based on lifting tasks and trunk rotations, their role in performance in acrobatic, combat, power and water sports should also be investigated. The number of participants in research studies should be increased. The research studies should include more elite athletes. In such a case, adults should be preferred over young participants. The number of female participants should be increased. The control group should be included, especially in intervention studies. Information on the degree of physical development of athletes and their exposure to sport-specific tasks should be included. Better understanding the role of postural and core stability in athletic performance requires testing under conditions specific to a particular sport. Therefore, testing under sport-specific conditions should be preferred, particularly in athletes at a high level of competition. Corresponding variables should be better specified in relation to functional movements in sports with high demands on postural and core stability. Studies investigating the association of postural and core stability with functional movement and performance in athletes should be carried out during a period of their high level of sport-specific skills. The duration of training sessions and training programs should be separately specified for balance exercises and core stabilization or core strengthening exercises. Greater attention should be paid to the interpretation of findings. Further research is needed to investigate the relationship between postural or core stability and sport-specific performance and their changes after sport-specific training.

Gaps and limitations revealed in the literature

Suggestions for future studies

There is a lack of studies investigating the relationship between core stability or core strength and functional movement and/or athletic performance.

There is still inconsistent definition of core stability and core strength in spite of an increased number of studies in this field of research.

The research in this field has been conducted mainly in shooting, biathlon, archery, gymnastics, and team sports. More research has been carried out in team than individual sports.

Small sample sizes occur in most studies, which could reduce its power and increase the margin of error.
There are only few studies conducted on competitive athletes of a high performance level. The analysis of the literature in this scoping review related to the role of core stability in functional movement and/or athlete performance revealed that nine studies (69%) were conducted with regularly competing high school or university athletes or athletes from lower competitions (Stanton et al., 2004; Abt et al., 2007; Chaudhari et al., 2011; Saeterbakken et al., 2011; Ozmen, 2016; Anand et al., 2017; Kuhn et al., 2019; Felion and DeBeliso, 2020; de Bruin et al., 2021), three studies (23%) with young elite athletes (Nesser et al., 2008; Nesser and Lee, 2009; Vitale et al., 2018), and one study (8%) with very young athletes (Sannicandro and Cofano, 2017).
Regarding the age of participants, eight studies (62%) included adult athletes (Abt et al., 2007; Nesser et al., 2008; Nesser and Lee, 2009; Chaudhari et al., 2011; Ozmen, 2016; Anand et al., 2017; Kuhn et al., 2019; de Bruin et al., 2021) and five studies involved young athletes (Stanton et al., 2004; Saeterbakken et al., 2011; Sannicandro and Cofano, 2017; Vitale et al., 2018; Felion and DeBeliso, 2020).
There is a lesser number of research studies conducted on female than male participants.
Regarding gender, the analysis of the literature related to the role of core stability in functional movement and/or athlete performance revealed that eight studies (62%) included male athletes (Stanton et al., 2004; Abt et al., 2007; Nesser et al., 2008; Chaudhari et al., 2011; Ozmen, 2016; Anand et al., 2017; Vitale et al., 2018; Felion and DeBeliso, 2020), four studies (31%) female athletes (Nesser and Lee, 2009; Saeterbakken et al., 2011; Kuhn et al., 2019; de Bruin et al., 2021), and one study (7%) both girls and boys (Sannicandro and Cofano, 2017).
The control group is rarely included. Non-sporting population cannot be included in most of the studies because of the athletic performance tests used.
There is a missing information on the level of athlete performance.

General physical fitness tests rather than sport-specific tests are used.

Variables analyzed are not precisely described.

Experiments are conducted in different training periods (pre-season, in-season, post-season) what limits a comparison of findings.

The average duration of training programs is from 4 to 8 weeks while the training sessions vary from 25 to 30 min, in some cases even from 60 to 75 min, which very often combine balance, strength and core muscle exercises.

There is insufficient analysis of neuromuscular mechanisms underlying significant associations of postural and core stability with functional movement and/or athlete performance.

Balance, strength, plyometric or endurance exercises are usually associated with training induced improvements of postural and core stability but not with athlete performance.

In comparison with balance research, more attention should be paid to investigations related to the role of core stability and core strength in functional movement and/or athletic performance.
The authors should use uniform terminology of core stability and core strength based on their characteristics, similarly as it is in the case of balance research.
As core stability and strength represent an integral part of athlete performance in sports based on lifting tasks and trunk rotations, their role in performance in acrobatic, combat, power and water sports should also be investigated.
The number of participants in research studies should be increased.
The research studies should include more elite athletes. In such a case, adults should be preferred over young participants.

The number of female participants should be increased.

The control group should be included, especially in intervention studies.
Information on the degree of physical development of athletes and their exposure to sport-specific tasks should be included.
Better understanding the role of postural and core stability in athletic performance requires testing under conditions specific to a particular sport. Therefore, testing under sport-specific conditions should be preferred, particularly in athletes at a high level of competition.
Corresponding variables should be better specified in relation to functional movements in sports with high demands on postural and core stability.
Studies investigating the association of postural and core stability with functional movement and performance in athletes should be carried out during a period of their high level of sport-specific skills.
The duration of training sessions and training programs should be separately specified for balance exercises and core stabilization or core strengthening exercises.
Greater attention should be paid to the interpretation of findings.

Further research is needed to investigate the relationship between postural or core stability and sport-specific performance and their changes after sport-specific training.