Investigating the effect of smartphone addiction on musculoskeletal system problems and cognitive flexibility in university students

Abstract

BACKGROUND:

Smartphone usage has become more common in daily life, and in certain situations, this may lead to addictive behavior.

OBJECTIVE:

This study aims to investigate the relationship between smartphone addiction and musculoskeletal problems and cognitive flexibility in university students.

METHODS:

Smartphone addiction was evaluated with the Smartphone Addiction Scale (SAS), the Nordic Musculoskeletal Questionnaire (NMQ) was used to evaluate musculoskeletal symptoms, and pain was measured with Visual Analog Scale (VAS). Cognitive flexibility was assessed with the Cognitive Flexibility Inventory (CFI).

RESULTS:

A significant correlation was found between SAS total score and musculoskeletal problems in the upper back, lower back, hip and feet (p < 0.05, r = 0.11; r = 0.16; r = 0.11; r = 0.13, r = 0.14). Smartphone addiction showed a significant positive correlation with neck pain, right hand pain and right arm pain (p < 0.05, r = 0.13; r = 0.17; r = 0.14). There was a significant negative correlation between CFI total score and SAS total score (p < 0.05, r = – 0.13).

CONCLUSIONS:

Smartphone addiction is associated with musculoskeletal problems, pain and cognitive flexibility in university students. Encouraging an active lifestyle, physical activity, ergonomic arrangements, individual behavioral modification as well as environmental regulations and policies may eliminate the negative effects of smartphone addiction.

Keywords

Cognitive flexibility musculoskeletal pain smartphone addiction

1. Introduction

Smartphone usage has become more common in daily life as a result of improved features and broadened usage areas. Smartphone addiction has beenconceptualized as a behavioral dependency [1, 2]. Studies show that this addiction is associated with behavioral problems including inactive lifestyle, musculoskeletal problems, pain, anxiety, compulsive behavior, control deficiency, sleep disorders, func-tional disorder and tolerance problems [3, 4]. Dep-endency behavior leads to changes in cognitive processes as well [5].

Musculoskeletal problems arise from long-term exposure to certain physical factors including recurrent movements, vibration, unsuitable stance or force. These problems may be acute, chronic and recurrent, thereby accepted as public health problems [6, 7]. While several studies have investigated the relationship between smartphone addiction and musculoskeletal problems, they have often focused on upper extremity problems [8, 9]. However, taking into account that parts of the body are interconnected, any problem in any part may affect another region adversely [10]. Therefore, it is important to evaluate the whole body in terms of musculoskeletal problems among smartphone users.

Cognitive flexibility refers to the mental proce-sses in which individuals restructure their mental resources in a different order. This skill enables the individual to adapt themselves to various situations rapidly and efficiently. Such an adaptation is cri-tical for strategic decision-making [11 –13]. However, there is very limited information about the mechanism underlying this skill or its effects on performance [14].

To date, several studies have investigated the relationship between smartphone usage and cognitive functions [15, 16]. One of these studies associated mobile phone usage with faster and less accurate responses to high-level cognitive tasks [15]. In another study [16], increased smartphone usage showed a correlation with more intuitive and less analytical thinking. The relationship between different addiction types (e.g. smoking, drug abuse, internet addiction and gambling) and low cognitive flexibility has been shown in the literature [17 –20]. However, to the best of our knowledge, there is no study thus far aiming to determine the relationship between smartphone addiction and cognitive flexibility.

Considering that humans are biopsychosocial, eva-luation of this addiction behavior, which also has health effects from different aspects with a holistic approach, may provide a guide for the intervention methods to be planned to eliminate the addiction behavior. The present study aims to investigate the relationship between smartphone addiction and musculoskeletal problems and cognitive flexibility in university students.

2. Methods

2.1. Participants and procedure

A total of 325 university students from Trakya University, Faculty of Health Sciences were included in the study. The inclusion criteria were being 18–25 years of age and using a smartphone for at least one hour per day. Subjects with any diagnosis of musculoskeletal system disorders were excluded from the study. The Ethical Committee Approval was obtained from Trakya University Social Sciences and Humanities Research Ethics Committee. Written informed consent was obtained from all participants.

Sociodemographic information (such as age and gender) and habits of the participants (such as smoking, regular physical exercise, usage of smartphone, social media and computer usage) were recorded.

Smartphone addiction was evaluated with the Smartphone Addiction Scale (SAS) [21]. SAS is a reliable and valid measurement tool for the evaluation of smartphone addiction developed by Kwon et al. in 2013 [22], and the Turkish version of SAS was used in this study [21]. This scale consists of 33 items and 7 factors including f1: disturbing daily life and tolerance, f2: withdrawal symptoms, f3: positive anticipation, f4: cyberspace-oriented relationships, f5: overuse, f6: social media dependence, f7: physical symptoms. A higher total score in this instrument indicates a higher risk of smartphone addiction.

The Turkish version of the Nordic Musculoskeletal Questionnaire (NMQ) was used to determine musculoskeletal problems [23]. NMQ consists of 3 questions related to 9 anatomic regions including the neck, shoulders, writs/hands, upper back, lower back, hip/thigh, knees and ankles/feet. The first question (Q1) is ‘Have you had any problems (ache, pain, discomfort) at any time within the last 12 months in (the relevant body part)?’; the second question (Q2) is ‘In the last 12 months, have you felt any limitation while carrying out daily activities?’; and the last question (Q3) is ‘Have you had any problems or pain in the last 7 days?’. All questions are scored as ‘yes’ or ‘no’ for each region.

Pain was assessed with Visual Analog Scale (VAS) [24]. A 100-mm VAS, ranging from 0 (no pain) to 100 (very severe pain), was used to measure pain levels. A higher score indicates greater pain intensity. In the current study, participants were asked to mark how much pain they had on their hands, arms and neck during the day.

The Turkish version of the Cognitive Flexibility Inventory (CFI) was used to determine the cognitive flexibility level [25] developed by Dennis et al., [26] this questionnaire is a brief self-reported instrument with 20 items and 2 factors including alternatives and controls. A high total score on this scale indicates increased cognitive flexibility.

2.2. Analysis

The smallest sample size with 0.5 effect size, 5% type I error margin and 80% statistical power was calculated as 325 subjects. Statistical analysis was performed by using the IBM SPSS software for Windows 21.0 package program. Descriptive qualitative data are presented as number and percentage. Quantitative data were calculated as mean or median, with standard deviation. Correlation between quantitative variables and their significance were assessed using the non-parametric Spearman’s correlation coefficient. Type-1 error level was set at 0.05 for statistical significance.

3. Results

The study was completed with 325 individuals (243 female; 82 male). Descriptive characteristics of the participants are presented in Table 1.Musculoskeletal problems of the participants based on NMQ and mean VAS scores of pain are presented in Table 2.In the last 12 months, musculoskeletal problems were mostly experienced in the upper back (60.00%), neck (56.90%) and lower back (58.80%). Participants reported some limitations primarily with their lower back (15.10%) and upper back (11.70%) while carrying out daily activities over the last 12 months. The mostly reported sites of pain during the last 7 days were the upper back (40.00%), neck (39.10%), and lower back (35.40%).

Table 1
Descriptive characteristics of the participants

Descriptive characteristics Mean±SD

Age Years 20.04±1.78

Duration of smartphone usage Years 6.41±1.88

Computer usage in one day Hours 0.87±1.48

Social media usage in one day Hours 3.57±2.48

Smartphone usage in one day Hours 3.60±2.44

N (%)

Sex Female 243 (74.77)

Male 82 (25.23)

Body Mass Index (BMI) Underweight 58(17.80)

Normal weight 217 (66.80)

Overweight 45 (13.80)

Obese 5 (1.50)

Hand preference Right 302 (92.90)

Left 23 (7.10)

Smoking Yes 81 (24.90)

No 244 (75.10)

Hand use when Unilateral 288 (88.60)

typing a message Bilateral 37 (11.40)

Descriptive characteristics		Mean±SD
Age	Years	20.04±1.78
Duration of smartphone usage	Years	6.41±1.88
Computer usage in one day	Hours	0.87±1.48
Social media usage in one day	Hours	3.57±2.48
Smartphone usage in one day	Hours	3.60±2.44
		N (%)
Sex	Female	243 (74.77)
	Male	82 (25.23)
Body Mass Index (BMI)	Underweight	58(17.80)
	Normal weight	217 (66.80)
	Overweight	45 (13.80)
	Obese	5 (1.50)
Hand preference	Right	302 (92.90)
	Left	23 (7.10)
Smoking	Yes	81 (24.90)
	No	244 (75.10)
Hand use when	Unilateral	288 (88.60)
typing a message	Bilateral	37 (11.40)

Table 2

Musculoskeletal problems and pain assessment of the participants

	Q1: Had some problems (ache, pain, discomfort) in the last 12 months	Q2: In the last 12 months felt some limitations while carrying out daily activities	Q3: Had some problems or pain in the last 7 days
Musculoskeletal problems	N (%)	N (%)	N (%)
Neck	185 (56.90)	28 (8.60)	127 (39.10)
Shoulders	160 (49.20)	24 (7.40)	89 (27.40)
Elbows	27 (8.30)	11 (3.40)	11 (3.40)
Wrists/hands	131 (40.30)	28 (8.60)	71 (21.80)
Upper back	195 (60.00)	38 (11.70)	130 (40.0)
Lower back	191 (58.80)	49 (15.10)	115 (35.40)
Hip/thigh	58 (17.80)	15 (4.60)	27 (8.30)
Knees	80 (24.60)	26 (8.00)	38 (11.70)
Ankles/feet	91 (28.00)	25 (7.70)	47 (14.50)
VAS scores	Right	Left
	Mean±SD	Mean±SD
Hand	1.83±2.08	0.89±0.46
Arm	1.89±2.15	0.14±0.71
Neck	3.20±2.62

The relationship between smartphone addiction and musculoskeletal problems, upper extremity pain and cognitive flexibility are shown in Table 3. A significant but weak correlation was observed between SAS total score and musculoskeletal problems in the upper back, lower back, hip and feet (p < 0.05, r = 0.11; r = 0.16; r = 0.11; r = 0.13, r = 0.14). A significant but weak positive correlation was detected between smartphone addiction and pain in the neck, right hand and right arm (p < 0.05, r = 0.13; r = 0.17; r = 0.14). There was a significant, weak and negative correlation between SAS total score and CFI total score (p < 0.05, r = – 0.13).

Table 3

The relationship between smartphone addiction and musculoskeletal problems, upper extremity pain and cognitive flexibility

		Smartphone Addiction Scale (SAS)
		f1		f2		f3		f4		f5		f6		f7		SAS total
		r	p	r	p	r	p	r	p	r	p	r	p	r	p	r	p
Neck	Q1	0.16	0.003	– 0.00	0.891	– 0.03	0.506	– 0.07	0.181	0.02	0.612	– 0.03	0.518	0.22	<0.001	0.05	0.358
	Q2	0.07	0.207	0.01	0.823	0.00	0.997	0.00	0.995	0.08	0.127	– 0.00	0.950	0.09	0.090	0.02	0.688
	Q3	0.12	0.024	– 0.01	0.780	– 0.02	0.643	– 0.07	0.510	0.06	0.262	– 0.03	0.521	0.166	0.003	0.06	0.219
Shoulders	Q1	0.10	0.057	0.04	0.467	0.01	0.813	– 0.00	0.977	0.02	0.653	– 0.06	0.248	0.186	0.001	0.04	0.421
	Q2	0.09	0.095	0.06	0.269	0.02	0.644	0.03	0.566	– 0.01	0.754	– 0.03	0.580	0.101	0.069	0.06	0.243
	Q3	0.07	0.181	– 0.03	0.510	– 0.03	0.588	0.01	0.850	– 0.00	70.881	– 0.12	0.027	0.179	0.001	0.01	0.803
Elbows	Q1	0.05	0.358	– 0.10	0.067	– 0.06	0.215	– 0.04	0.417	– 0.01	0.835	– 0.08	0.136	0.122	0.028	– 0.00	0.901
	Q2	0.03	0.508	– 0.00	0.992	0.00	0.877	– 0.01	0.860	– 0.03	0.535	– 0.06	0.275	0.113	0.041	0.03	0.571
	Q3	0.07	0.207	– 0.02	0.677	– 0.01	0.819	– 0.03	0.514	– 0.00	0.891	0.03	0.537	0.096	0.084	0.03	0.510
Hands	Q1	0.13	0.018	0.05	0.415	– 0.02	0.647	0.05	0.314	0.01	0.842	0.02	0.725	0.163	0.003	0.05	0.345
	Q2	0.07	0.157	– 0.02	0.606	0.00	0.995	– 0.02	0.709	0.03	0.577	0.00	0.873	0.077	0.166	– 0.00	0.939
	Q3	– 0.01	0.770	– 0.00	0.949	0.01	0.861	0.03	0.517	0.01	0.787	– 0.09	0.094	0.058	0.300	– 0.01	0.745
Upper back	Q1	0.13	0.013	0.01	0.861	0.05	0.293	– 0.04	0.430	0.01	0.728	0.02	0.645	0.095	0.088	0.07	0.202
	Q2	0.08	0.116	0.04	0.452	0.03	0.496	0.07	0.174	0.10	0.072	– 0.00	0.870	0.174	0.002	0.10	0.051
	Q3	0.15	0.007	0.06	0.238	0.04	0.384	0.05	0.293	0.06	0.251	0.05	0.349	0.045	0.417	0.11	0.034
Lower back	Q1	0.21	<0.001	0.04	0.467	0.10	0.057	0.09	0.079	0.07	0.206	0.05	0.312	0.190	0.001	0.16	0.003
	Q2	0.12	0.023	0.06	0.227	0.01	0.746	– 0.02	0.708	0.09	0.094	0.06	0.285	0.177	0.001	0.11	0.036
	Q3	0.11	0.044	0.04	0.429	0.08	0.129	0.04	0.427	0.01	0.807	– 0.03	0.571	0.151	0.007	0.10	0.072
Hip/thigh	Q1	0.12	0.020	0.06	0.234	0.09	0.105	0.03	0.514	0.05	0.343	0.04	0.395	0.169	0.002	0.13	0.015
	Q2	0.11	0.037	0.00	0.965	– 0.01	0.761	0.05	0.321	0.00	0.991	0.05	0.307	0.101	0.070	0.09	0.085
	Q3	0.03	0.537	– 0.01	0.832	0.04	0.449	0.03	0.555	– 0.01	0.815	– 0.01	0.790	0.061	0.277	0.04	0.469
Knees	Q1	0.07	0.165	0.04	0.450	0.11	0.043	0.03	0.541	0.04	0.472	– 0.00	0.870	0.127	0.022	0.08	0.126
	Q2	0.05	0.358	0.04	0.468	– 0.02	0.699	0.00	0.938	– 0.05	0.310	0.01	0.850	0.088	0.116	– 0.00	0.983
	Q3	– 0.01	0.731	– 0.01	0.857	0.07	0.211	0.00	0.892	– 0.05	0.301	– 0.00	0.941	0.072	0.198	0.01	0.855
Ankles/feet	Q1	0.13	0.016	0.13	0.016	0.10	0.060	0.12	0.026	0.09	0.088	0.05	0.335	0.089	0.110	0.14	0.009
	Q2	0.00	0.969	– 0.01	0.742	– 0.04	0.416	0.06	0.272	0.03	0.560	0.05	0.338	0.017	0.763	0.01	0.860
	Q3	0.08	0.138	– 0.02	0.657	0.05	0.364	0.03	0.560	0.02	0.631	0.02	0.653	– 0.005	0.923	0.05	0.290
Right hand VAS		0.22	<0.001	0.13	0.013	0.09	0.093	0.04	0.429	0.09	0.106	0.04	0.459	0.258	<0.001	0.17	0.002
Right arm VAS		0.18	0.001	0.07	0.157	0.06	0.255	0.00	0.895	0.00	0.872	0.00	0.879	0.201	<0.001	0.14	0.011
Left hand VAS		0.05	0.307	0.10	0.063	– 0.08	0.112	0.14	0.010	– 0.02	0.612	0.08	0.143	0.115	0.038	0.06	0.212
Left arm VAS		0.04	0.450	0.06	0.235	– 0.13	0.018	0.12	0.028	– 0.05	0.331	0.04	0.379	0.099	0.075	0.03	0.490
Neck VAS		0.15	0.004	0.05	0.311	0.05	0.288	0.02	0.672	0.09	0.099	– 0.04	0.388	0.285	<0.001	0.13	0.014
CFI total		– 0.17	0.05	– 0.21	<0.001	– 0.03	0.595	– 0.15	0.004	– 0.06	0.252	– 0.07	0.210	– 0.13	0.016	– 0.13	0.018

Q1: Had some problems (ache, pain, discomfort) in the last 12 months; Q2: In the last 12 months felt some limitations while carrying out daily activities; Q3: Had some problems or pain in the last 7 days.

4. Discussion

The present findings indicate that smartphone addiction is associated with musculoskeletal problems, pain, and cognitive flexibility. With increased smartphone addiction, increased musculoskeletal problems and pain are observed while cognitive flexibility tends to decrease.

In general, musculoskeletal problems especially in the neck, upper back and lower back were related to smartphone addiction in this study. This is reasonable and expected due to several reasons. Firstly, the incorrect posture including but not limited to tilting the head forward while using a smartphone may cause problems and pain in cervical and spinal regions [27, 28]. Secondly, smartphone usage results in long-term sitting and static stance, which may increase the risk of upper and lower back pain [29]. Another likely reason is that smartphone usage requires actions such as making calls, texting, using social media and the internet, which may result in sedentary behavior [30], and adversely affect the physical activity level [31, 32]. In addition; present findings indicate that smartphone addiction is not only associated with problems of the upper extremities, but also with that of the trunk and lower extremities. These results highlight the importance of the notion that any musculoskeletal problem should be evaluated by adopting a holistic approach and by taking into account the biomechanical properties of the human body.

It has been reported that individuals with high a level of electronic device usage more frequently complain about musculoskeletal system problems and pain in cervical and thoracolumbar regions [33]. The present study showed an association between smartphone addiction and pain in the upper extremities and the neck. In particular, there was a relationship between smartphone addiction and pain in the neck, right hand and right arm according to the current study results. Considering almost all of the participants used their right hand dominantly; this result was not unexpected. In general, almost all functions of smartphones require individuals to keep their head and neck in flexion position or arms in front of them to view the screen [27]. In a study evaluating musculoskeletal symptoms among mobile hand-held device users, most participants reported pain in at least one body part, and pain in the right hand was most common at the base of the thumb [34]. In another study, almost all subject stated that they use smartphone with one hand. Lee et. al. determined that there was higher muscle activity in abductor pollicis, extensor pollicis longus and upper trapezius in smartphone users using one hand than those using both hands [35]. Considering previous studies and the current findings in terms of pain prevention and management, several preventive approaches should be planned, such as ensuring correct posture to reduce musculoskeletal disorders, advice on how to use smartphones in order to reduce muscle load, ergonomic trainings, etc.

The present study showed that increased usage of smartphones is also related to cognitive flexibility. Smartphone addiction may have negative effects on cognitive flexibility due to associated sedentary behavior. In literature, sedentary behavior is associated with impaired cognitive function independent from exercise [36, 37]. There is also some evidence to suggest that exercise may reduce some of the detrimental effects of sedentary behavior on cognition [38]. Therefore, reducing sedentary behavior and maintaining an active lifestyle may be considered as a measure to be taken to maintain and improve cognitive flexibility.

Another important issue in this regard is the fact that cognitive flexibility may affect university stu-dents’ ability to consider different academic proces-ses during their undergraduate period and explore various career options [39]. Adams et al. [40] determined that first-year college students with higher levels of cognitive flexibility report stronger professional identity than those with lower cognitive flexibility. These findings show that cognitive flexibility may affect confidence and career choices. Therefore, cognitive flexibility is important for students to be academically successful and creative, and make better career choices. When the literature findings and results of this study are taken into consideration; taking precautions regarding the use of smartphones proves to be necessary in order to prevent the unfavorable effects on cognitive flexibility.

The present study has certain strengths. Firstly, whole body was evaluated in terms of musculoskeletal problems, and it was concluded that smartphone addiction is not only associated with upper extremity problems, but also with those concerning the neck, trunk and lower extremities. Secondly, this is the first study investigating the relationship between smartphone addiction and musculoskeletal problems and cognitive flexibility.

There are also some limitations of this study. The first limitation is the assessment of cognitive flexibility using an inventory tool. The second limitation may be the female-male ratio of the study sample. Due to the widespread use of smartphones, especially beginning from an early age, future studies should be planned to cover different age groups.

5. Conclusion

Smartphone addiction is associated with musculoskeletal problems, pain and cognitive flexibility in university students. Musculoskeletal problems and pain increase while cognitive flexibility decreases with increased smartphone addiction. Therefore, encouraging an active lifestyle, physical activity, ergonomic arrangements, individual behavioral modification methods as well as environmental regulations and health policies may eliminate the negative effects of smartphone addiction. Individual and social awareness should be increased, especially in relation to the features of smartphones likely to increase participation in physical activity (e.g. use of pedometer and reminders for physical activity or drinking water).

Conflict of interest

The authors declare that they have no conflict of interest.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

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