Loading...

Baby-wearing. A study on the transmission of motion in different transport modalities

Master's Thesis 2014 43 Pages

Physical Therapy / Occupational Therapy

Excerpt

Inhaltsverzeichnis

Introduction
Background
Consequence
Objectives
Hypothesis
Relevance

Methods and materials
Recruitment
Participants
Data
Randomization
Anthropological data
Measures with the Polhemus Liberty™
Preparation of the motion - sensors

Results
Data Analysis
Statistical analysis of repetitions
Statistical analysis of conditions

Discussion
Walking with the baby-dummy free
Usage of the Baby- Carrier, Baby-Björn
Usage of the Baby Sling
General perspective

Conclusion

Bibliography

Appendices

Acknowledgement

I would like to express my deepest gratitude to my supervisors. A first special Thank You goes to Prof. Dr. D. Vissers who encouraged me to explore this topic and guided me throughout the development and process of this thesis. A second special Thank You goes to Prof. Dr. J.-P. Baeyens whose contribution to the content of this thesis was very precious, as for the setting of the laboratory facilities and conducting the measurements as for the evaluation of the data and statistics. And finally a very special Thank You goes to Dr. Ron Clijsen, whose engagement especially during the recruitment and data collection contributed to the extent and conduction of my trials and made them possible in a very smooth way. I did enjoy the process and work with you three.

I also like to express my gratitude to Andreas Ratzek at ADAC e.V. Technikzentrum, who supported this study by providing the baby-dummy during measurements. Also, I like to thank the participants in my survey, who have willingly shared their precious time during the trials.

A Thank you goes to Franziska G. for providing me access to all full text articles via the University Freiburg.

Thanks to the Library Staff of the University Freiburg who offered me a free 24/7 access to the Lesesaal where I found solitude and a perfect environment to read and write during the last two years.

Finally I like to thank my parents from heart for the precious support and assistance, which gave me the energy and the time to finalize this work.

Abstract

Background Beneficial physiological effects have been attributed to Baby - Wearing. These effects have been related mainly to two components: first the close skin-to-skin contact and second the consistent movement during carriage. Although the designated effects have been related in an important proportion to the movements, nobody has investigated the quality of these movements yet. This study was performed to explore the movement of the baby‘s body during locomotion in different methods of transport.

Objective The objective of this study is to investigate the varying range of motion (ROM) between the mother and the carried baby during one gait cycle in different types of transport.

Methodology A total sample size of 25 participants (f=20, m=5) were assessed. Anthropometrical data was collected. Mean age was 30,8 ±11,19 years, mean height was 1,71 ±0,085 meters and mean weight was 67,5 ±11,9 kgs. Mean BMI was calculated as 22,82 ±2,55 kgs/sqt bodyhight (cm²).

A course of 3 meters was determined within a laboratory setting and the Polhemus Liberty (PolhemusTM , Colchester, Vermont; US, Canda, 2008) was calibrated. The setting was identical in all runs. The trials were conducted in randomized order. The participants were asked to carry the baby-dummy in three specified transportation methods: in a Baby-Sling

(BS), in a Baby-Classic Carrier (BC) and holding the baby on their arm (BF). The thoracic cage movement was measured in both, mother and child, during carriage in each method. Outcome The results showed up with statistically significance for the comparisons of the ROMs between BS and BC (p= .043) as well as for the ROMs between BC and BF (p= . 038). No other parameters in this evaluation presented statistically significant differences in ROM. The magnitude (cm) of the significant results was 2,13 and 3,2 respectively.

Conclusion With regard to the magnitude of these findings, and from a practical point of view, it is assumable that each tested transport modality represents in a real life environment no relevant distinguishable qualities relating to the ROM between the mother and the worn child as presented by the analysis of the motion differences within one gait cycle.

Keywords Baby-wearing, baby-transport, range of motion analysis, ROM, difference.

Introduction

Background

Baby transport plays a central and ever present role in parent‘s all day living. Especially daily tasks as physical activity and social participation demand potential mobility from parents and caregivers.

Said to be beneficial and as a fast growing and popular alternative to a stroller[18], baby wearing celebrates its revival into modern lifestyles. Uncoupled from the reputation of being a practice in poor and alternative cultures, this original practice of baby transport grows through the influence of the modern pop culture. Baby wearing is an actual trend with a fast growing acceptance on every social level. And deservedly so.

Investigation on the usage of baby carriers has shown that they retrieve a lot of benefits concerning the baby’s health compared to the common baby transport by strollers or baby buggies. The list of benefits attributed to baby wearing is growing, since research on that topic began already in the late nineteen - eighties. It has been found that worn babies compared to those who are transported in a buggy or equivalent transporter show facilitated development and important benefits on structural [4, 5, 10, 11], neurobehavioral [2, 3, 5, 7, 8, 9, 12, 14, 15] and social level. Beside that, the parent’s proximity helps children to regulate their state[20]and develop a deep bond together [1, 7, 10, 16, 17, 18].

These facts could be supported by biological examinations affirming an evolution affected adaption of the human body and the forming of genetically endowment which makes the infants body highly compatible to be worn[10].

Behavioral evidence lies in the neonatal reflex patterns. They provide the instant ability to attach to the mothers body for a new born right after delivery[5].

To highlight the physiological benefits, which contribute to a healthy and stable state of the infant, the impact of Baby Wearing on these benefits has been examined in several studies[6]. Wearing a baby does not only facilitate the adoption to the world outside the mother’s body but additionally increases immunological protection. It could have been demonstrated that baby‘s who are to often separated to the mother, as for example those who lie immoderate periods in a stroller or cradle, did show of with different behavioral patterns and are more prone to illnesses compared to babies who were most of the time attached to their parents. An evident explanation for this effect is, that the close body - contact during baby wearing decreases the amount of the toxic stress hormone cortisol in the baby‘s blood and therefor allows a steady production of leucocytes maintaining an intact immune function[13].

Furthermore, that the baby’s wellbeing is increased through close attachment strategies has been reflected in specific investigations. A popular parameter for these examinations has been the “Crying behavior”. It has been shown that worn babies cry less compared to those who has been carried separated from the mother [2, 3, 9, 12, 14, 17]. Researchers found correlation between Baby Wearing and the mental and the emotional development. They detected, that it is the sensual stimulation during wearing, which effects the mental state and allows a better ability to learn and receive from the environment [5, 19, 21].

Still, individuals who were worn as Baby, and thereby received a close attachment during their first years, profit by their parenting experience. Worn babies sample the feeling of security and trust, attached to the mothers body, which could have been contributed to an appropriate independency to the caregivers at earlier ages [6, 17, 19].

illustration not visible in this excerpt

(table 1, Table of benefits)

All these advantages of baby wearing have been related mainly to two components: on the one side the close skin-to-skin contact from the mother to her child and on the other side the consistent movement during carriage[19].

Consequence

Although, the designated advantages have been related in a significant proportion to the movements, the baby receives during carriage, nobody yet has investigated the quality of these movements.

This study is performed to bridge this gap of knowledge and analyze the movement of the baby‘s body during locomotion in different methods of transportation.

Objectives

The objective of this study is to evaluate and analyze the varying range of motion (ROM) between the mother‘s and the carried baby during gait in different types of transport. The goal is to find out how the infant’s body moves during transportation in reference to the carrying person.

Hypothesis

Related to the investigated movement parameters, it is hypothesized that, first, there is no difference between the three methods of baby wearing and second, there is no difference in each method compared to the related gait parameters of the carrying person.

Relevance

The results of this study will pour in the knowledge to the movement mechanisms and kinematics of baby wearing. Moreover, it will answer the question on movement transmission appearing during the different baby‘s transport modalities and the variance in range of motion (ROM) between the mother and the carried baby. Thereby this study will bridge this gap of knowledge. After all this study may provide the basis for further research.

Methods and materials

Recruitment

Students and staff from the University of Applied Sciences and Arts of Southern Switzerland (SUPSI) were contacted and informed about this research (see Appendix 1). The need for participants has been announced and students who wanted to participate and who met the inclusion criteria were recruited and scheduled.

Participants

A total sample size of 25 participants (female=20,male=5; age(y)=30,8 ±11,19; height(cm)=1,71 ±0,085; weight(kg)=67,5 ±11,9; BMI=22,82 ±2,55) volunteered to take part in the study (table 2).

All subjects gave their informed consent prior to the conduction of the measurement (see Appendix 2).

Since no vital values had to be examined the baby was replaced by a Baby Dummy (Model: K.AI - P3/4 Child Dummy. Humanetics Innovative Solutions Plymouth, USA.) The dummy was equal to a baby of 9 month[22]. (weight(kg)=9; hight(cm)=70)

illustration not visible in this excerpt

(table 2, Table of subjects)

Data

Randomization

To provide for best comparability between the different methods of baby carriage, the order in which the measurement was conducted had been randomized. For randomizing the sequence of the tests, the participants were assigned to one of two equal sized groups (Group1; Group2). Group affiliation was allocated according to the order of their appearance in the laboratory. This model allowed a balanced data collection. The measurement was conducted in the sequence related to the participant’s group-number (table 3).

illustration not visible in this excerpt

(table 3, Table of random groups and *number of allocated subjects)

Anthropological data

Hight was measured (cm) in a standardized upright standing position using an anthropometer (GPM Anthropological Instruments, DKSH Switzerland Ltd.); Weight was measured using a Tanita weight balance (TBF-612 Body Fat Monitor/Scale, Tanita Europe GmbH, Germany). BMI was calculated and age and gender were included on the data sheet.

Measures with the Polhemus Liberty™

The motion was captured using the Polhemus Liberty™,an electromagnetic motion capturing device. The Polhemus Liberty™ consists of one transmitter and sensors. The transmitter emits an electromagnetic field, wherein the sensors, suited on the inside with orthogonal coils, detect the orientation and motion.[23]

For the Polhemus Liberty™ (Polhemus , Colchester, Vermont; US, Canda, 2008) measurement the device was installed and calibrated. The course wherein the measurements were conducted was determined to be 3 meters. Start and endpoints were marked. 1,5 meters space before and behind the start and stop had been marked. Within this space the participant started and stopped walking respectively (see Appendix 3). The given instruction for the participant was: „Walk at a comfortable pace“. The participant performed 3 walks per session and all three walks were captured using the Polhemus Liberty™.

Preparation of the motion - sensors

The participants were equipped with two sensors of the Polhemus Liberty™device (PolhemusTM , Colchester, Vermont; US, Canda, 2008). The sensors were attached one to the manubrium and one to the left heel. The sensors were fixed on the skin using a double-faced adhesive tape between the skin and the sensors as well as an adhesive tape to fix the sensors in a sheltered way to secure their positioning during movement.

The Baby Dummy was suited with one sensor on the back of its thorax - area. The sensor was fixed in the same way as described before.

The participants were asked to walk with the baby in the three transportation methods as described in table three (table 4).

illustration not visible in this excerpt

(table 4, methods of transport.)

At the end of the procedure the sensors were replaced from the participants and it was taken leave from each.

Results

There were assessed 25 healthy individuals who voluntarily participated in this study. None of them presented any condition of impairment and was physiologically and mentally able and willed to participate in this trial. None of the participants was pregnant or obese, which are circumstances that would have contributed to difficulties for the baby’s attachment to the body. No participant was excluded from participating in this study. Anthropometrical data was collected as in table 2 was demonstrated. Mean age was 30,8 ±11,19 years, mean height was 1,71 ±0,085 meters and mean weight was 67,5 ±11,9 kgs. BMI was calculated for each individual and the statistical mean of the sample‘s BMI has been calculated as 22,82 ±2,55 kgs/sqt bodyhight (cm²).

illustration not visible in this excerpt

*table 2, Table of subjects

illustration not visible in this excerpt

(table 6, Table of descriptive statistics)

illustration not visible in this excerpt

Chart 1, mean differences between the different transport modalities (A, B and F), standard deviations and 95% confidence intervals, in cm.

illustration not visible in this excerpt

Chart 2, mean differences between the repetitions (1, 2 and 3) for each tested transport modalities (A, B and F), standard deviations and 95% confidence intervals, in cm.

Data Analysis

The designated outcome of the collected data (table 6, chart 1 & 2) represents the translation of the thorax sensor of the baby in terms of the thorax sensor of the carrier as it was followed during the observed gait intervals (1,2,3) for each tested device (A,B,F). The output value ‚max-min‘ is described as the mean differences, its standard deviation and the 95% confidence interval. It reports the mean difference of the motion between the thorax sensor of the carrier and the thorax sensor of the baby. The data is reported in centimeters.

These values were collected and analyzed using the MatCad Software (Version 2 PTC® ). The asked gait interval was identified manually, and its data prepared for further analysis in Microsoft Excel. In Microsoft Excel the factorsmean,standard deviation (stddevs), localminimum (min)andmaximum (max)as the range of motion(ROM) (max-min) were calculated applying the predefined algorithms to the data. Using SPSS (Version 20, IBM) a multifactorial ANOVA has been performed and enabled to analyze and interpret the data for each factor. Based on the research question the demanded outcome was the valuemax-min, which referred to the range of motion (ROM). The following section summarizes the output data and statistical analysis, which were performed for this value on the factors repetition and condition, wherein repetition signifies the type of transportation (BS, BC, BF) and the condition tags the repetition of each trial (i.e. A1,A2,A3).

Statistical Analyses

illustration not visible in this excerpt

table 7, ANOVA

illustration not visible in this excerpt

table 8, pair wise comparison

Statistical analysis of repetitions

A repeated measures ANOVA was conducted to determine whether there were statistically significant differences between the three repetitions and accordingly types of transportation. The three repetitions elicited statistically significant differences among themselves F= 3,236, p= .048, partial η2 = 0.119. Mauchly's Test of Sphericity indicated that the assumption of sphericity had not been violated, χ2(2) = 4,222, p = .121. Post-hoc analysis with a Fisher‘s least significant difference test and no adjustments revealed that between the repetitions was statistically significant difference in ROM from rep 1 (BS) to rep 2 (BC) (M = 2,126 cm, 95% CI [0.07 to 4,18], p =.043), and from rep 2 (BC) to rep 3 (BF) (M = 3,19 cm, 95% CI [6,19 to 0,19], p = .038) but not from rep 1 (BS) to rep 3 (BF)(M = 1,065 cm, 95% CI [3,83 to 1,70], p = .434).

Statistical analysis of conditions

The conducted repeated measures ANOVA determined whether there were statistically significant differences between the conditions of the three repetitions. The assumption of sphericity was violated, as assessed by Mauchly's Test of Sphericity, χ2(2) = 20,06, p < . 05. Therefore, a Huynh-Feldt correction was applied (ε = 0.651).

[...]

Details

Pages
43
Year
2014
ISBN (eBook)
9783656866350
ISBN (Book)
9783656866367
File size
1.1 MB
Language
English
Catalog Number
v286356
Grade
3,0
Tags
baby-wearing

Author

Share

Previous

Title: Baby-wearing. A study on the transmission of motion in different transport modalities