Martin Zvonar

Dr. Martin Zvonar


Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 October 2022 in International Journal of Hygiene and Environmental Health
Verified
Journal Article
Open access
RLRosa Lange
Rosa Lange
VNVogel Nina
Vogel Nina
PSPhillipp Schmidt
Phillipp Schmidt
AGAntje Gerofke
Antje Gerofke
MLMirjam Luijten
Mirjam Luijten
MKMarike Kolossa-Gehring
Marike Kolossa-Gehring

MKMario Kasović
Mario Kasović
LŠLovro Štefan
Lovro Štefan
MZMartin Zvonar
Martin Zvonar
Although it has been well-documented that older adults spend a significant amount of time being sedentary and have slower gait velocity, little is known of how physical fitness mediates the association between them. The main purpose of this study was to explore whether objectively measured physical fitness mediates the association between domain-specific and total sedentary behavior and gait velocity. We recruited 120 older adults aged ≥ 60 years. Sedentary behavior was assessed by the Measure of Older Adults’ Sedentary Time questionnaire. We used a Zebris pressure platform to assess gait velocity. To assess the level of overall physical fitness, we summed the z-scores of seven tests: (1) waist circumference, (2) chair stand in 30 s, (3) arm curl in 30 s, (4) 2-min step test, (5) chair sit-and-reach test, (6) back scratch test, and (7) 8-foot up-and-go test. Overall physical fitness was obtained by summing up all physical test z-scores. Gait velocity was significantly associated with all domain-specific and total sedentary behavior (β = −0.04 to −0.35, p < 0.05). Overall physical fitness was significantly associated with all domain-specific and total sedentary behavior (β = −0.21 to −1.24, p < 0.001) and gait velocity (β = 0.23 to 0.24, p < 0.001). When physical fitness was put as the mediator, significant direct effects between sedentary behavior and gait velocity disappeared. Results indicate that physical fitness fully mediates the association between sedentary behavior and gait velocity in older adults.

MKMario Kasović
Mario Kasović
LŠLovro Štefan
Lovro Štefan
KBKrunoslav Borovec
Krunoslav Borovec
MZMartin Zvonar
Martin Zvonar
JCJan Cacek
Jan Cacek
The main purpose of the study was to explore the effects of carrying police equipment on spatiotemporal and kinetic gait parameters. Two-hundred and seventy-five healthy men and women attending police academy (32% women) were randomly recruited. Gait analysis without and with a police equipment load (≈3.5 kg) was analyzed using the Zebris pressure platform. Differences and effect sizes were calculated using a Student t-test and Wilcoxon test for dependent samples and Cohen’s D statistics. In both men and women, carrying police equipment significantly increased the foot rotation (effect size 0.13–0.25), step width (0.13–0.33), step time (0.25), stride time (0.13–0.25) and peak plantar pressure beneath the forefoot (0.16–0.30), midfoot (0.15–0.32) and hindfoot (0.13–0.25) region of the foot. Significant reductions in the step length (0.12–0.25), stride length (0.14–0.23), cadence (0.15–0.28) and walking speed (0.20–0.22) were observed in both sexes. Although significant, the effect sizes were mostly trivial in men and small in women. Our study shows significant changes in the spatiotemporal and kinetic gait parameters when carrying police equipment for both men and women. Although the effect sizes are trivial to small, carrying police equipment of ≈3.5 kg may have a negative impact on gait characteristics in first-year police officers.

12 February 2022 in Children
Verified
Journal Article
Open access
PDF file
VVVeronika Vasilcova
Veronika Vasilcova
MAMoqfa AlHarthi
Moqfa AlHarthi
NANadrah AlAmri
Nadrah AlAmri
PŠPeter Šagát
Peter Šagát
Peter BartikPeter Bartik
Peter Bartik
MZMartin Zvonar
Martin Zvonar
(1) Background: The objective of this study was to assess the prevalence of Developmental Dysplasia of the Hip (DDH) as a primary or secondary diagnosis during physiotherapy practice. No other studies have investigated the prevalence and associations of DDH within the practice of pediatric rehabilitation. (2) Methods: This retrospective review was performed on 12,225 physiotherapy referrals to the King Abdullah Specialized Children’s Hospital (KASCH), Riyadh, Kingdom of Saudi Arabia, from May 2016 to October 2021. Only DDH referrals for conservative treatment were included in the study. The plan for brace treatment was carried out by the pediatric orthopedics clinic in KASCH. The diagnostic methods were either a pelvic radiograph or ultrasound, depending on the participant’s age. DDH is considered one of the most common secondary complications for children with other medical diagnoses. (3) Results: The most common indication for referral was neurological diagnosis (44%), followed by orthopedic (28%), genetic (19%), cardiac (5%), ophthalmologic (3%), dermatologic (1%) and rheumatologic (0.5%) diagnoses. (4) Conclusion: The prevalence of DDH among all referrals in this study was 6%. In physiotherapy practice, neurologic, genetic, and orthopedic primary or secondary diagnoses were the most prevalent when DDH referrals were investigated. A relatively high prevalence of DDH in the pediatric rehabilitation clinic at KASCH in Riyadh was reported in this study.

MZMartin Zvonar
Martin Zvonar
MKMario Kasović
Mario Kasović
LŠLovro Štefan
Lovro Štefan
Background. The main purpose of this study was to explore the body-mass index and waist circumference associated with physical fitness by gender. Methods. In this cross-sectional study, we included 1036 adolescents (55.4% girls) from eight randomly selected secondary schools within the city of Zagreb (Croatia). Body-mass index and waist circumference were objectively measured. Physical fitness included three tests: (1) 1 min sit-ups, (2) standing long jump and (3) a sit-and-reach test. Associations were calculated using linear regression models. Results. Boys had higher body-mass index and waist circumference values, compared to girls (p < 0.001). They also performed better in 1 min sit-ups and the standing long jump tests (p < 0.001), while girls obtained higher values in the sit-and-reach test (p < 0.001). In boys, body-mass index and waist circumference were associated with 1 min sit-ups and the standing long jump. In girls, waist circumference was also associated with 1 min sit-ups and the standing long jump, while body-mass index was only associated with this standing long jump. Conclusions. Our study shows that anthropometric indices have non-linear associations with physical fitness tests in a large sample of Croatian adolescents. Screening for thinness and obesity to predict the level of physical fitness should be of a great interest.

SCStanisław Czyż
Stanisław Czyż
MZMartin Zvonar
Martin Zvonar
ZBZbigniew Borysiuk
Zbigniew Borysiuk
JNJiří Nykodým
Jiří Nykodým
POPiotr Oleśniewicz
Piotr Oleśniewicz
There are a limited number of studies focusing on the mechanisms explaining why variable practice gives an advantage in a novel situation and constant practice in performance in trained conditions. We hypothesized that this may be due to the different gaze behavior that is developed under different conditions. Twenty participants, randomly assigned to two different groups, practiced basketball free throws for three consecutive days, performing 100 throws per day. The constant group (n = 10) practiced at a free throw distance (4.57 m) only. The variable practice group (n = 10) randomly performed 20 shots per five throw distances (3.35, 3.96, 4.57, 5.18, and 5.79 m) on each day, also accumulating 100 shots per day. We analyzed the total gaze fixation duration, a number of fixations, and the average fixation duration on a basketball rim in a pretest and posttest at the 4.57 m distance. We computed a linear mixed model with test (pretest–posttest), group (constant–variable), and test × group interaction in order to analyze the total fixation duration and number of fixations. The average fixation duration was analyzed with a repeated measure two-way ANOVA, with practice conditions as a between-participants factor and test type as a within-participants factor. We found that the total fixation duration increased significantly in the posttest, regardless of the practice conditions (p < 0.001, effect size = 0.504). The number of fixations also increased significantly in the posttest (p = 0.037, effect size = 0.246). The average fixation duration increased in both groups; however, insignificantly. We also did not find any significant differences between groups. Our results suggest that variable and constant practice conditions may lead to the development of similar gaze behavior.