A vocational rehabilitation intervention for young adults with physical disabilities: participants' perception of beneficial attributes.

BACKGROUND: Finding and maintaining employment is a major challenge for young adults with physical disabilities and their work participation rate is lower than that of healthy peers. This paper is about a program that supports work participation amongst young adults with chronic physical disabilities. The study aims to explore their experienced barriers and facilitators for finding and maintaining employment after starting this program, the participant-perceived beneficial attributes of the program and participants' recommendations for additional intervention components. METHODS: Semi-structured interviews (n = 19) were held with former intervention participations. Interviews were recorded and transcribed ad verbatim. Themes were derived using the phenomenological approach. RESULTS: Physical functions and capacities, supervisor's attitude, self-esteem and self-efficacy and openness and assertiveness were experienced barriers and facilitators for finding and maintaining employment. Improvement of self-promoting skills and disclosure skills through job interview-training, increased self-esteem or self-efficacy through peer-support, a suitable job through job placement, improvement of work ability through arrangement of adjusted work conditions and change of supervisor's attitude through education provided to the supervisor were perceived as beneficial attributes of the intervention. Respondents recommended to incorporate assertiveness and openness skills training into future intervention programs. CONCLUSIONS: The findings suggest that programs supporting work participation should be designed to provide challenging, real-world experiential opportunities that provide young adults with physical disabilities with new insights, self-efficacy and life skills. Also, such programs should facilitate context centered learning. Former intervention participants, therefore, evaluated job-interview training, sharing learning and social experiences with peers, job placement, arrangement of adjusted work conditions and education as beneficial attributes of the 'At Work' program. In addition, they recommended, to incorporate more training on assertiveness and disclosure. We advise professionals to include these beneficial attributes in similar interventions in other contexts.

A lifestyle intervention improves fatigue, mental health and social support among adolescents and young adults with cerebral palsy: focus on mediating effects.

OBJECTIVE: To evaluate the effect of a lifestyle intervention on fatigue, participation, quality of life, gross motor functioning, motivation, self-efficacy and social support, and to explore mediating effects of physical behavior and physical fitness. DESIGN: A randomized controlled trial with intention to treat analysis. SETTING: Rehabilitation centers in university hospitals in the Netherlands. SUBJECTS: Adolescents and young adults with spastic cerebral palsy. INTERVENTIONS: A six-month lifestyle intervention that consisted of physical fitness training combined with counseling sessions focused on physical behavior and sports participation. MAIN MEASURES: Fatigue, social participation, quality of life and gross motor functioning. RESULTS: The lifestyle intervention was effective in decreasing fatigue severity during the intervention (difference = -6.72, p = 0.02) and in increasing health-related quality of life with respect to bodily pain (difference = 15.14, p = 0.01) and mental health (difference = 8.80, p = 0.03) during follow-up. Furthermore, the domain participation and involvement of the social support increased during both the intervention (difference = 5.38, p = 0.04) and follow-up (difference = 4.52, p = 0.03) period. Physical behavior or physical fitness explained the observed effects for 22.6%, 9.7% and 28.1% of improvements on fatigue, bodily pain and mental health, but had little effect on social support (2.6%). INTERPRETATION: Fatigue, bodily pain, mental health and social support can be improved using a lifestyle intervention among adolescents and young adults with cerebral palsy. Furthermore, substantial mediating effects were found for physical behavior and physical fitness on fatigue, bodily pain and mental health.

Youth with acquired brain injury in The Netherlands: a multi-centre study.

UNLABELLED: Abstract Aim: To describe the occurrence and causes of acquired brain injury (ABI), including traumatic brain injury (TBI) and non-traumatic brain injury (NTBI), among Dutch youth and estimate incidence rates from the data. PATIENTS: Aged 1 month-24 years, hospital diagnosed with ABI in 2008 or 2009. METHODS: In three major hospitals in the southwest region of the Netherlands patients with ABI were retrospectively identified by means of diagnosis codes and specific search terms. RESULTS: One thousand eight hundred and ninety-two patients were included: 1476 with TBI and 416 with NTBI. Causes of TBI and NTBI varied among the age groups 0-4, 5-14 and 15-24 years, with accidents (in traffic or at home) being the most common cause of TBI and hypoxic-ischemic events for NTBI, in all groups. The estimated yearly incidence rates per 100 000 for mild-moderate-severe TBI were 271.2-15.4-2.3 (0-14 years) and 261.6-27.0-7.9 (15-24 years), for mild-moderate-severe NTBI they were 95.7-11.8-1.3 (0-14 years) and 73.8-6.1-1.6 (15-24 years), respectively. CONCLUSION: More than 15% of TBI and NTBI in children and youth is classified as moderate or severe, with causes of TBI and NTBI varying among age groups. Based on the occurrence of ABI in three hospitals, the estimated incidence of ABI in children and youth in the southwest region of the Netherlands is substantial.

Physical fitness, everyday physical activity, and fatigue in ambulatory adults with bilateral spastic cerebral palsy.

This study assessed physical fitness and its relationships with everyday physical activity (PA) and fatigue in cerebral palsy (CP). Participants were 42 adults with ambulatory bilateral spastic CP (mean age 36.4 ± 5.8 years; 69% males; 81% with good gross motor functioning). Progressive maximal aerobic cycle tests determined VO(2peak) (L/min). Objective levels of everyday PA were measured with accelerometry and self-reported levels of everyday PA with the Physical Activity Scale for Individuals with Physical Disabilities. Fatigue was assessed with the Fatigue Severity Scale. The average aerobic capacity of adults with CP was 77% of Dutch reference values. Participants were physically active during 124 min/day (85% of Dutch reference values), and half experienced fatigue. In women, lower physical fitness was related to lower self-reported levels of PA (R(p)=0.61, P=0.03), and in men to higher levels of fatigue (R(p)=-0.37, P=0.05). Other relationships were not significant. Results suggest that ambulatory adults with CP have low levels of physical fitness, are less physically active than able-bodied age mates and often experience fatigue. We found little evidence for relationships between the level of physical fitness and everyday PA or fatigue.

Functional activities of the upper extremity of young adults with cerebral palsy: a limiting factor for participation?

PURPOSE: To assess functional activities of the upper extremity of young adults with cerebral palsy (CP) and to determine their relations with participant characteristics and participation. METHOD: Assessment of functional activities of the upper extremity was performed on 103 participants (aged 16-20 years) with the Melbourne assessment and the Abilhand Questionnaire. Participation was measured with the Life Habits Questionnaire. Participant characteristics included age, gender, limb distribution of the spastic paresis, educational level and gross and fine motor function. Relations among these variables were studied by means of correlation coefficients and linear regression analysis. RESULTS: Limitations in functional activities of the upper extremity were related to the limb distribution of the spastic paresis and were especially present in quadriplegic participants. Significant correlations between participant characteristics and measures of functional activities were present. Limitations in functional activities of the upper extremity, measured with the Abilhand Questionnaire, were an important determinant for participation, in addition to the gross motor function and educational level. CONCLUSION: Limitations in functional activities of the upper extremity are an important determinant for restrictions in participation in young adults with CP. It is recommended to include assessment of functional activities of the upper extremity in patients with CP.

Energy cost and physical strain of daily activities in adolescents and young adults with myelomeningocele.

The aim of this study was to assess the energy cost and physical strain of daily activities in adolescents and young adults with myelomeningocele (MMC) compared with peers without a disability. Eighteen participants with MMC aged between 16 and 30 years (13 males, five females; mean age 21y 4mo [SD 4y 8mo]) and 18 age- and sex-matched non-disabled participants performed several standardized activities. Energy cost was assessed by oxygen uptake expressed per unit time (all activities) and per metre (walking and wheelchair use at preferred speed). Physical strain was calculated by dividing energy cost by aerobic capacity. For all activities no difference was found in energy cost per unit time between ambulatory participants with MMC and comparison participants. Energy cost per metre walking at preferred speed in participants with MMC was 0.26ml/kg/m (SD 0.08), and in comparison participants was 0.20ml/kg/m (SD 0.03); p=0.08. Non-ambulatory participants with MMC had lower energy cost (per unit time and per metre) during wheelchair use than comparison participants during walking (p<0.05). For most activities, physical strain was 1.4 to 2 times higher in participants with MMC than in comparison participants (p<0.05). In conclusion, energy cost per unit time of daily activities was not increased in participants with MMC. However, energy cost per metre during walking at preferred speed and physical strain were higher than in peers without disability.

Cognitive functioning of adolescents and young adults with meningomyelocele and level of everyday physical activity.

PURPOSE: To explore whether cognitive functioning in patients with meningomyelocele (MMC) is related to level of everyday physical activity. METHOD: In a cross-sectional study in 14 patients with MMC (aged 14 - 26 years) a neuropsychological test battery was administered to each patient. Everyday physical activity of the patients was measured with an accelerometry-based Activity Monitor (AM), and compared to 14 healthy comparison subjects. RESULTS: Intellectual ability of 10 patients was in the normal range. For memory and verbal learning, executive functioning, divided attention and reaction speed subnormal scores were present in six or more patients. Time spent on dynamic activities was low in patients with MMC as compared to healthy subjects. After controlling for intellectual ability, we found that in patients with MMC (i) executive functioning was positively related, and (ii) word production was negatively related to everyday physical activity. CONCLUSION: We found some indication that specific impairments in executive functioning might be related to everyday physical activity of adolescents and young adults with MMC.

Reliability and sensitivity to change of measurement instruments used in a traumatic brain injury population.

OBJECTIVE: To compile a minimum data set for the follow-up of traumatic brain injury patients from discharge from hospital to one year post injury to assess functioning and participation in the physical, cognitive and psychosocial domains, and in quality of life. DESIGN: Repeated questionnaire interviews by two observers to establish inter-observer reliability of the measurement instruments at discharge and at one year post injury, as well as their sensitivity to change over time in traumatic brain injury patients. SETTING: Department of neurosurgery of an academic hospital, department of a rehabilitation centre, and at the patients' homes in the Netherlands. SUBJECTS: The study at discharge included 25 patients aged 18-50 years with a moderate to severe traumatic brain injury (Glasgow Coma Scale score 3-14), whereas the one year post injury study included 14 patients aged 19-51 years. MAIN (OUTCOME) MEASURES: Physical domain: Barthel Index (BI), Functional Independence Measurement (FIM), Glasgow Outcome Scale (GOS), GOS Extended (GOSE). Cognitive domain: Disability Rating Scale (DRS), Functional Assessment Measurement (FAM), Levels of Cognitive Functioning Scale (LCFS), Neurobehavioural Rating Scale (NRS). Psychosocial domain: Community Integration Questionnaire (CIQ), Employability Rating Scale (ERS), Frenchay Activity Index (FAI), Multi Health Locus of Control (MHLC), Rehabilitation Activities Profile (RAP), Social Support List (SSL), Supervision Rating Scale (SRS), Wimbledon Self Reporting Rating Scale (WSRS). Quality of life: Coop/Wonca Charts (Coop), Rand SF-36 (Rand-36), Sickness Impact Profile-68 (SIP-68). RESULTS: At both discharge and at one year post injury, in the physical domain the FIM showed excellent squared weighted kappa (SWK ranging from 0.75 to 0.80), and intraclass correlation coefficient (ICC ranging from 0.75 to 0.92), and a relatively small standard error of measurement (SEM 3.22) and smallest detectable difference (SDD 8.92). In the cognitive domain the FAM and the NRS showed excellent SWK, and ICC, and a relatively small SEM and SDD. In the psychosocial domain the FAI showed excellent SWK (0.89), and ICC (0.87), and a relatively small SEM (2.64) and SDD (7.31). For quality of life, at both discharge and at one year post injury the SIP-68 and the Coop showed excellent SWK (0.87), and ICC (0.89), and a relatively small SEM (3.79) and SDD (10.51). At both time points SWK and ICC ranged from 0.80 to 0.89, SEM ranged from 1.47 to 1.98, and the SDD was 4.07. CONCLUSIONS: An example of a reliable minimum data set that is also able to detect changes over time is: the FIM, the FAM and the Coop for the early stages in recovery, extended with the NRS, the FAI, and the SIP-68 later in recovery, thereby covering all relevant domains after traumatic brain injury.

Responsiveness of isokinetic dynamometry parameters, pain and activity level scores to evaluate changes in patients with capsulitis of the shoulder.

OBJECTIVE: To determine the responsiveness to change of isokinetic dynamometry of the shoulder and to compare this responsiveness with outcome measures of pain and activity level. DESIGN: Responsiveness was evaluated as the change in outcome after intra-articular steroid injection in patients with capsulitis of the shoulder. Effect sizes of all outcome measures, quantified as standardized response means, were compared. Relationships between change scores of shoulder function and activities were assessed. SUBJECTS: Ten patients with unilateral capsulitis of the shoulder. MAIN OUTCOME MEASURES: Muscle strength and active range of motion were measured by isokinetic dynamometry. We then calculated involved/uninvolved ratios of the maximal peak torques of abduction, adduction, external and internal rotation, active range of motion of abduction and external rotation. In addition, pain was scored using the numeric rating scale (NRS-101) and activity level was scored using the Shoulder Disability Questionnaire. RESULTS: The standardized response mean of all outcome parameters was equal to or greater than 0.8, except for active range of motion of abduction. No significant differences between the standardized response means were found. There is a significant correlation between the change scores of NRS-101 and Shoulder Disability Questionnaire. No significant correlations were found between the change scores of NRS-101 and Shoulder Disability Questionnaire on the one hand, and involved/ uninvolved ratios of peak torques and active range of motion on the other. CONCLUSIONS: Responsiveness of all outcome measures is good. Parameters of isokinetic dynamometry may provide additional information as compared with the usual outcome measures of pain and functional level.

The compangle: a new goniometer for joint angle measurements of the hand. A technical note.

The accuracy of joint angle measurement of the hand may be negatively influenced by joint swelling, deformation and other obstacles. We developed an alternative goniometer with clear ergonomic advantages, especially for the measurement of small joints. This new concept of goniometry is described and preliminary results on the reliability of the measurements are presented. The intraclass correlation coefficients (ICCs) and the standard error of measurements (SEMs) of the alternative goniometer are greater respectively smaller than a conventional goniometer, indicating a better intratester reliability.

Everyday physical activity in adolescents and young adults with meningomyelocele as measured with a novel activity monitor.

We measured the extent of hypoactivity in adolescents and young adults with meningomyelocele with an activity monitor. The activity monitor is based on long-term ambulatory monitoring of signals from body-fixed accelerometers during everyday life and is aimed at the assessment of mobility-related activities. Measurements were performed during 2 consecutive weekdays in 14 patients with meningomyelocele (aged 14 to 26 years) and in 14 matched, healthy subjects. Mean duration of dynamic activities (composite measure) was less in the patients (6.5 +/- 2.3%) than in comparison subjects (12.7 +/- 4.3%, P =.001). Number of walking or wheelchair-driving periods was 122 +/- 48 in the patients and 185 +/- 65 in the comparison subjects (P =.01). Resting heart rate was higher in the patients (70 +/- 7 beats/min vs 64 +/- 5 beats/min, P =.01). Time spent with dynamic activities was correlated with ambulatory status (r(s) = 0.55, P <.05). Adolescents and young adults with meningomyelocele, particularly the nonambulators, are considerably hypoactive.

Smallest real difference, a link between reproducibility and responsiveness.

The aim of this study is to show the relationship between test-retest reproducibility and responsiveness and to introduce the smallest real difference (SRD) approach, using the sickness impact profile (SIP) in chronic stroke patients as an example. Forty chronic stroke patients were interviewed twice by the same examiner, with a 1-week interval. All patients were interviewed during the qualification period preceding a randomized clinical trial. Test-retest reproducibility has been quantified by the intraclass correlation coefficient (ICC). the standard error of measurement (SEM) and the related smallest real difference (SRD). Responsiveness was defined as the ratio of the clinically relevant change to the SD of the within-stable-subject test-retest differences. The ICC for the total SIP was 0.92, whereas the ICCs for the specified SIP categories varied from 0.63 for the category 'recreation and pastime' to 0.88 for the category 'work'. However, both the SEM and the SRD far more capture the essence of the reproducibility of a measurement instrument. For instance, a total SIP score of an individual patient of 28.3% (which is taken as an example, being the mean score in the study population) should decrease by at least 9.26% or approximately 13 items, before any improvement beyond reproducibility noise can be detected. The responsiveness to change of a health status measurement instrument is closely related to its test-retest reproducibility. This relationship becomes more evident when the SEM and the SRD are used to quantify reproducibility, than when ICC or other correlation coefficients are used.

The use of therapeutic ultrasound by physical therapists in Dutch primary health care.

BACKGROUND AND PURPOSE: The purposes of this study were to describe the use of ultrasound by Dutch physical therapists and to address the question of whether this use is what would be considered correct. SUBJECTS AND METHODS: Physical therapists in the Dutch primary health care system gathered data on 17,201 patients, addressing reasons for referral, treatment goals (in terms of impairments and disabilities), and physical therapy interventions. Patients treated with ultrasound (n = 3,959) were compared with a reference group of patients who were not treated with ultrasound (n = 13,242). RESULTS: Physical therapists applied ultrasound for soft tissue injuries of recent onset, mainly aiming to reduce pain and swelling. Ultrasound was used in all phases of treatment and was not restricted to the first 3 weeks of treatment. Ultrasound was combined relatively infrequently with exercise and relatively frequently with massage. CONCLUSION AND DISCUSSION: Regarding the indications for referral and treatment goals chosen, the actual use of ultrasound corresponds to assumptions about expected use. The timing of its application and the combination with other forms of therapy do not correspond in all aspects to the assumptions made.

Reliability assessment of isometric knee extension measurements with a computer-assisted hand-held dynamometer.

OBJECTIVE: To assess clinically relevant indexes of measurement error of hand-held dynamometer measurements using a computer-assisted hand-held dynamometer (CAHN-DY). DESIGN: In separate sessions, different physical therapists performed repeated measurements of maximal isometric knee extension. SETTING: Four physical therapy practices and outpatient departments. PATIENTS: Consecutive samples of 30 male and 28 female patients aged 13 to 77 years, with isolated orthopedic knee disorders participated in this study. MAIN OUTCOME MEASURES: For intrarater and interrater applications, the standard error of measurement (SEM) and related 95% confidence intervals and minimal detectable changes were assessed. RESULTS: Sixty percent of the patients performed within the therapist's upper force limit. Variance between sessions performed by the same or different therapists accounted for a large percentage of the measurement error (70% to 81%). For single measurements, the standard error of measurement was assessed not to exceed 10N x m. Minimal detectable changes for different designs varied from 13.8 to 28.2N x m. CONCLUSIONS: The CAHN-DY facilitated standardization of test performance in a satisfactory manner, resulting in less measurement error compared with simple hand-held dynamometry.

Computer-assisted hand-held dynamometer: low-cost instrument for muscle function assessment in rehabilitation medicine.

In rehabilitation medicine, muscle function is assessed during the physical examination of the patient. Although a simple hand-held instrument improves the assessment of static strength, it is rarely used in clinical practice, where dynamic measurements are preferred. A computer-assisted hand-held dynamometer (CAHNDY) has been developed that enables the clinician to measure dynamic muscle function in a standardised manner, using simple (i.e. portable and low-cost) apparatus. The CAHNDY comprises a force transducer and a movement transducer interfaced to a personal computer. In the study dynamic measurement protocols are used, based on a biomechanical analysis of daily activities. In this way, iso-functional profiles can be established, describing the kinematics of muscle function in its functional context. Using the iso-functional profiles as a basis for standardisation, the double feedback algorithm of the CAHNDY assists the tester in meeting this standard, during maximal muscle function testing. In a multi-centre trial, the CAHNDY is evaluated by physical therapists for knee extensor and flexor function. The CAHNDY enables iso-functional dynamic muscle function testing, although application is limited by the maximal strength of the tester. It is concluded that the CAHNDY is suitable for use in rehabilitation medicine.

Measuring functional limitations in rising and sitting down: development of a questionnaire.

OBJECTIVE: Develop and test a self-administered questionnaire that measures perceived and actual functional limitations in rising and sitting down. SETTING: Private practices for physical therapy and outpatient clinics of hospitals and rehabilitation centers. PATIENTS: 345 outpatients (43% male, aged 14 to 92 years) with different grades of functional limitations and different types of lower extremity orthopedic or rheumatologic disorders. METHODS: The Questionnaire Rising and Sitting Down (QR&S) was developed on the basis of a literature review and careful operationalization of functional limitations. Five dimensions concerning different objects (high chair, low chair, toilet, bed, and car) and one global dimension were postulated to be contained in the instrument. Mokken scale analysis was used to test the postulated dimensions (scalability coefficient H). Furthermore, robustness with respect to patient characteristics was determined, as well as intratest reliability (reliability coefficient Rho), test-retest reliability (intraclass correlation coefficient [ICC]), content validity (coverage of operationalized aspects), and construct validity (testing of seven hypotheses). RESULTS: Mokken scale analysis confirmed the existence of 5 object dimensions (H = .53-.59). However, two global dimensions were found (H = .50-.54). The resulting hierarchical scales, consisting of subsets of the 32 final QR&S items, are robust and measure functional limitations in a reliable (Rho .77-.91; ICC .72-.90) and valid (3 out of 4 aspects covered, 2 hypotheses rejected for 3 out of 7 scales) manner. CONCLUSION: The QR&S is a reliable and valid self-administered questionnaire. It consists of hierarchical scales and measures perceived and actual functional limitations in rising and sitting down.

Two strategies of transferring from sit-to-stand; the activation of monoarticular and biarticular muscles.

In this study, two different strategies of rising from a chair were compared, using integrated biomechanical and electromyographic analyses. Nine healthy subjects were instructed to rise using two different strategies: natural sit-to-stand transfer (NSTS) and a sit-to-stand transfer with full flexion of the trunk (FSTS). Sagittal kinematics and ground reaction forces were registered. Muscle activity of nine muscles of the right leg were recorded by means of surface EMG. All signals were synchronized at seat-off. The results show that no differences occur between the kinematics of knee and ankle, whereas the hip flexion is, as expected, higher during FSTS. The higher moment about the knee during NSTS is shifted to proportionally higher moments about the hip and ankle during FSTS. It is mainly the differences in the EMG-levels of the biarticular hip and knee muscles which might explain the differences in net moment. These results are in accordance with a theory about a particular role of biarticular muscles. On the other hand, the shift from knee to ankle cannot be associated with a particular increase in activity of the biarticular m.gastrocnemius. It is hypothesized that about the ankle, control of stability is preferred over movement control. An important conclusion for rehabilitation medicine is that a lower net moment about the knee in FSTS does not automatically imply that this reduces the load on the knee extensors.

Biomechanics and muscular activity during sit-to-stand transfer.

In the present study 10 healthy subjects were measured, performing sit-to-stand transfers in a natural way. Starting position and speed of movement were standardized. Sagittal kinematics, the ground reaction force, and muscle activity of nine leg muscles were recorded. During sit-to-stand transfer the mass centre of the body was moved forward and upward. Based on the velocity of the mass centre of the body three phases were distinguished. In horizontal direction forward rotation of the upper body contributed to the velocity of the mass centre of the body, whereas extension of the legs contributed considerably in vertical direction. After seat-off most muscles were concentrically active, whereas the shortening velocity of the rectus femoris was very low. Thus hip and knee joints were extended and a relatively high knee moment was delivered to control the ground reaction force in a slightly backward direction. Co-contraction of hamstrings and rectus femoris in sit-to-stand transfer was judged to be efficient.

The application of generalizability theory to reliability assessment: an illustration using isometric force measurements.

BACKGROUND AND PURPOSE: The objective of this study was to examine the potential use of the generalizability theory for assessing reliability of muscle force measurements in clinical applications. Reliability is expressed in terms of standard error of measurement (SEM) and the indexes derived from the SEM. Using generalizability theory, potential sources of measurement error can be recognized and estimated. SUBJECTS: Ten healthy women, aged 23 to 47 years (means = 29.5, SD = 7.1), participated in the study. METHODS: The method is illustrated by presenting a pilot study. Repeated measurements of maximal isometric knee extension force were carried out by two therapists. The time interval between measurement occasions was 1 week. A functional prototype of a hand-held dynamometer was used, and measurements were carried out according to standardized test protocols. RESULTS: Relatively important sources of measurement error were associated with interaction effects between subject and therapist as well as with interactions including the factor occasion. The SEM of the net knee moment was estimated for various hypothetical applications of the dynamometer. CONCLUSION AND DISCUSSION: It is concluded that the SEM, the corresponding confidence interval, and the smallest detectable difference are practical measures for expressing reliability of measurements on an individual. Generalizability theory is a powerful tool for estimating the magnitude of multiple sources of measurement error and for assessing the reliability of measurements tailored to specific clinical applications.

A comparison of one-legged and two-legged countermovement jumps.

Ten well-trained male volleyball players performed one-legged and two-legged vertical countermovement jumps. Ground reaction forces, cinematographic data, and electromyographic data were recorded. Jumping height in one-legged jumps was 58.5% of that reached in two-legged jumps. Mean net torques in hip and ankle joints were higher in one-legged jumps. Net power output in the ankle joint was extremely high in one-legged jumps. This high power output was explained by a higher level of activation in both heads of m. gastrocnemius in the one-legged jump. A higher level of activation was also found in m. vastus medialis. These differences between unilateral and bilateral performance of the complex movement jumping were shown to be in agreement with differences reported in literature based on isometric and isokinetic experiments.