Motivational Resistance-training Program on Adherence and Body Composition in Elderly
Condition: Motivation; Body Weight
MeSH terms: Body Weight
Study type: Interventional

Summary: 
      Lack of physical activity is one of the major causes for obesity and functional disability in
      the elderly. Including regular exercise in elderly´s lifestyle is not an easy task. The main
      objective was to analyse the effect of a motivational resistance-training programme on
      satisfying the individual´s psychological needs, level of self-determination and body
      composition. A quasi-experimental study was performed with 47 volunteers (29 females, 18
      males) of 67-75 years of age, divided into two groups: experimental (n = 27) and control (n =
      20). A 12-week intervention programme was performed, with a total of 36 sessions.
    

Detailed description: 
      Material and Methods

      Participants The study included a total of 47 subjects, (29 females, 18 males) ages 65 to 75
      years, recruited from an elderly social club. The participants were divided into two groups:
      experimental group (n=27; 10 men and 17 female) and control group (n=20; 8 men and 12
      female). The sampling was natural and intentional. All subjects originated from Murcia
      (Spain) and met the following inclusion criteria: had never previously attended classes in
      fitness academies or were not currently performing regular physical activity, and had no
      previous experience with resistance-training programmes. Exclusion criteria included any
      history of neuromuscular, metabolic, hormonal or cardiovascular diseases; not taking any
      medication that could influence hormonal and neuromuscular metabolism. In addition, the
      participants were advised to not alter their diet during the study. Participants were
      informed about the possible risks and discomforts that could arise and were asked to complete
      a health history questionnaire and sign a consent form. The current study was approved of the
      Ethics Committee of the Catholic University San Antonio of Murcia (Spain) following the
      guidelines of the Helsinki Declaration.

      Design A quasi-experimental design (2x2) was developed, dividing the participants into two
      groups; one experimental and one control. In this design, an initial measurement prior to the
      intervention (pre-test) and a measurement after the intervention (post-test) were conducted.
      This same research design has been used in previous studies, which has sought to assess the
      effect of an intervention programme on body composition, motivational variables and
      resistance-training.

      Data Collection and Procedure Motivational variables Behavioural regulation during exercise.
      The Spanish version of Behavioural Regulation during Exercise Questionnaire was used. This
      questionnaire allows to evaluate the type of motivational regulation related to physical
      exercise, and consists in 23 items distributed in three dimensions, based on the established
      distinction in the SDT between autonomous motivation, controlled motivation and demotivation.
      Autonomous motivation was calculated using the mean score of intrinsic regulation (e.g.
      "Because I think that exercise is fun"), integrated regulation (e.g. "Because I believe that
      physical exercise is consistent with my values") and identified regulation (e.g. "I value the
      benefits of exercise"). Each of these regulations was composed of 4 items, except for the
      identified regulations which was composed of 3 items. Controlled motivation was calculated
      using the mean score of introjected regulation (e.g. "I feel guilty when I don't exercise")
      and external regulation (e.g. "I feel under pressure from my friends/family to exercise")
      with 4 items each. Demotivation (e.g. "I don't see why I should have to exercise") was also
      calculated using 4 items. Previous research in the physical activity and health context
      demonstrated the internal reliability of the instrument.

      Basic psychological needs during exercise. To assess the perceived need satisfaction of the
      participants, the Spanish adaptation of the Basic Psychological Needs in Exercise Scale was
      used (BPNES), which is specific for the context of physical activity and health.67 The
      questionnaire includes 12 items distributed in three dimensions. Four items measure autonomy
      (e.g. "I exercise according to what I intend to do"), four items measure competence (e.g. "I
      feel that physical exercise is an activity that I do very well") and the other four items
      measure relatedness (e.g. "I have a close relationship with the people with whom I
      exercise"). Previous research in the physical activity and health context demonstrated the
      internal reliability of the instrument.

      The answers to the questionnaires were assessed on a Likert scale ranging from 1 to 7, where
      one corresponded with the anchor statement "strongly disagree" and seven with the anchor
      statement "strongly agree". Before carrying out the intervention, the main researcher
      contacted with the director of the social club to inform of the purpose of the study.
      Likewise, all the participants involved were informed about the process that they were going
      to follow, emphasizing that participation was voluntary. The researcher overviewed how to
      complete the questionnaire and answered any questions that arose during the process. The
      different questionnaires were completed in an adequate climate of concentration, with each
      participant taking approximately 15-20 minutes to complete the questionnaires.

      Body composition variables Total body weight was measured, after removal of shoes and heavy
      outer clothing, using a Tanita BC-418 MA scale, (Tanita Corporation, Arlington Heights, IL)
      to the nearest 0.1 kg.69 Standing height without shoes was measured using a Seca 202
      stadiometer (Seca, Hamburg, Germany) to the nearest 0.1 cm. To minimize the potential source
      of Bioimpedance systems (BIA) related to total body weight and height, body composition
      assessment was performed by a level two anthropometrist following International Society for
      the Advancement of Kinanthropometry recommendations.70 Body Mass Index (BMI) was calculated
      as the ratio of weight to squared height. BMI was categorized into underweight (<18.50
      kg/m2), normal weight (18.50-24.99 kg/m2), overweight (25.00-29.99 kg/m2), and obese (30.00
      kg/m2).

      Bioelectrical impedance was measured using the Tanita BC-418 MA scale, with participants
      standing barefooted on the analyser's footpads, and holding its handles. Fat mass (FM) and
      muscle mass (MM) were then calculated, using the prediction equation described by Jebb et al.
      Bioelectrical impedance was chosen due to its ease of use and less invasive nature, making it
      suitable for assessment of body composition in vulnerable populations such as obese
      individuals and elderly.

      Multi-dimensional intervention programme Prior to the commencement of the study, the subjects
      were submitted to two weeks of training, two sessions per week, in order to be familiarized
      with the resistance-training exercises performed in the current study. During this
      familiarization period, a higher emphasis was placed on learning the proper exercise
      techniques, and brief pauses between repetitions were allowed in order to reset their
      starting positions when necessary. During the second week of the familiarization period, a
      pre-test of the motivational variables was performed, as well as measuring weight, height,
      BMI, FM and MM. Both pre-test and post-test were carried out in one day between 8:00 and 9:00
      a.m. After the pre-test, the experimental group underwent a resistance-training programme for
      12 weeks, where different motivational strategies were used. The resistance-training
      programme incorporated resistance exercises of six major regions and consisted in 3 training
      sessions per week on non-consecutive days (Monday, Wednesday, and Friday). The six regions
      were chest, back, triceps, biceps, shoulders and legs. The different regions were grouped
      into a circuit. The control group, on the other hand, did not participate in the
      resistance-training programme.

      The experimental group exercised at a moderate intensity (8 to 12 repetitions). The load was
      increased during the 12 weeks from 65% 1-RM to 80% 1-RM. This training load was increased
      when the individual could perform more than the prescribed number of repetitions (12
      repetitions), following the OMNI-RES scale and a hard effort perception level. A 1-2 minutes
      resting period was allowed between sets.

      All training sessions were monitored by an experienced physical education professional and
      the subjects were not allowed to perform any additional exercises during the training period.
      During the training weeks, participants were instructed not to change dietary habits or
      perform additional non-resistance-training related physical activity.

      In addition, with the objective of increasing the adherence to the resistance-training
      programme, a series of motivational strategies were performed.

      The strategies to motivation assessment used were based on the principles of the
      Self-Determination Theory (SDT). SDT includes a meta-theory for framing motivational studies,
      a formal theory that defines intrinsic and varied extrinsic sources of motivation, their role
      in cognitive and social development, as well as in individual differences. SDT is a theory of
      motivation and personality that addresses three universal, innate and basic psychological
      needs: autonomy, competence and relatedness. During the resistance-training programme, the
      subjects received verbal motivational strategies, based on previous studies which have proven
      the beneficial effect they exert on BPN satisfaction and autonomous motivation.
    

Intervention name(s): Motivational resistance-training programme
Intervention type(s): Other
Intervention description(s): The experimental group exercised at a moderate intensity (8 to 12 repetitions). The load was increased during the 12 weeks from 65% 1-RM to 80% 1-RM. This training load was increased when the individual could perform more than the prescribed number of repetitions (12 repetitions), following the OMNI-RES scale and a hard effort perception level.74 A 1-2 minutes resting period was allowed between sets. During the sessions, the participants were verbally encouraged to perform the complete range of motion for each exercise and received motivational strategies.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Intervention model description: A quasi-experimental design (2x2) was developed, dividing the participants into two groups; one experimental and one control. In this design, an initial measurement prior to the intervention (pre-test) and a measurement after the intervention (post-test) were conducted. The sampling was natural and intentional.
Masking: Single (Investigator)
Primary purpose: Basic Science
Keywords: elderly; motivation; adherence; resistance-training; health