Although contrasting evidence exists in the literature as to the economy of head-loading, there is a notion that head-loading is an extremely economical method of load carriage. This has become known as the 'free ride' hypothesis and, although untested, it is widely accepted. The purpose of this study was to test the 'free ride' hypothesis for head-load carriage among African women by comparing the relative economy of head-loading and back-loading. Twenty-four Xhosa women walked on a level treadmill, attempting to carry loads of between 10% and 70% of their body mass (BM) using both a backpack and a head basket. All 24 women carried at least 25% of their BM in both conditions. The relative economy of load carriage was calculated for loads of 10% to 25% of BM. Results indicated that the 'free ride' was not a generalisable phenomenon, with both methods realising economy scores close to unity (1.04 ± 0.19 and 0.97 ± 0.15 for head-loading and back-loading, respectively). The results did, however, reveal significant individual differences in economy scores and it is suggested that analysis of such individual differences in future may well be instructive in understanding mechanisms associated with greater economy in load carriage.http://www.sajs.co.za

The purpose of this study was to compare the subjective perceptual responses to both head-loading and back-loading in a group of Xhosa women. Thirty two women were divided into three groups based on their experience of head-loading and walked on a treadmill on two occasions, head-loading and back-loading, at a self selected walking speed for 4 min with a variety of loads until pain or discomfort caused the test to be terminated or a load of 70% body mass was successfully carried. After each workload there was a 1 min rest period during which the women indicated feelings of pain or discomfort in particular areas of the body via visual analogue scales. At the end of each test the women were asked to complete further questionnaires relating to pain and discomfort and on completion of the second test were also asked to compare the two loading conditions. Finally the women were interviewed to establish their history of load carriage and associated pain and discomfort. The data indicate that whilst back-loading was generally associated with more areas of discomfort than head-loading, the pain and discomfort in the neck associated with head-loading was the predominant factor in the termination of tests and that this was independent of head-loading experience. This early termination meant that, on average, the women could carry greater loads on their backs than on their heads. The study suggests that further work needs to be carried out to establish viable alternatives to head-loading for rural dwellers in Africa.

The research ethics committee (REC) is a key element of university administration and has gained increasing importance as a review mechanism for those institutions that wish to conduct responsible research, along with safeguarding research ethics standards, scientific merit and human rights of participants. Given the critical role of the university REC, it is argued that there is a need to assesses and understand the work of RECs to identify areas for improvement and thus focus on capacity building to respond to the escalating volume, type and complexity of research. This paper reports on the research ethics outcomes of a social science REC in a Business Faculty at a South African university during its seminal period of operation (2010–2015). Content methodology and a standardised questionnaire were used to assess the REC. The results show the increasing workload of the REC with favourable scores for submission/review processes and minute-taking. However, lower scores were seen for ethics education/training and tracking previously approved research. These shortcomings appear to be related to inadequate funding and resource support for research ethics education/training and administrative structures. Factors contributing to proposal rejections included weak research questions or hypotheses, poor questionnaires/interview schedule design and inadequate research ethics consideration in the proposal. It is argued that the complexity and escalation of research submissions to South African RECs necessitates that they are appropriately developed and capacitated to enhance their utility and thereby support the research mandate of universities.

This study investigated the energetics of walking on sand and grass. Fourteen adult males, participated in the study. Participants had a mean age of 34.6 years old, 72.6 kg in mass and 172.5 cm in stature, who walked at 3, 4, 5, 6 and 7 km per h on sand and grass surfaces. Physiological measures included heart rate, O(2) uptake, CO(2) exhalation, ventilation and relative O(2) uptake using a MetaMax Ergospirometer. Speed was controlled in a methodology similar to the 'Multistage 20-m Shuttle Run Test'. Data were collected during physiological steady rate at each determined speed. A minimum of 2 h rest was enforced between randomized conditions. Results indicate that there was a significant increase (p < 0.01) in all measured physiological indices indicative of energy expenditure when walking on sand compared to grass at 3-7 km per h, with the greatest disparity between the surfaces (ratio = 1.63) in relative O(2) consumption at 5 km per h.

Aim: to quantify the physiological cost of head-load carriage and to examine the 'free ride' hypothesis for head-load carriage in groups of women differing in their experience of headloading.Method: Twenty four Xhosa women (13 experienced head-loaders (EXP), 11 with no experience of headloading (NON)) attempted to carry loads of up to 70% of body mass (BM) on both their heads and backs whilst walking on a treadmill at a self selected walking speed. Expired air was collected throughout. In a second study nine women, members of the British Territorial Army (TA), carriedsimilar loads, again at a self selected speed.Results: Maximum load carried was greater for the back than the head (54.7±15.1% v 40.8±13.2% BM, P<0.0005). Considering study one, head-loading required a greater oxygen rate than back-loading (10.1±2.6 ml.kgbodymass -1 .min -1 v 8.8±2.3 ml.kgbodymass -1 .min -1 , P=0.043, for loads 10-25%BM) regardless of previous head-loading experience (P=0.333). Percentage changes in oxygen consumption associated with head-loading were greater than the proportional load added in both studies but were smaller than the added load for the lighter loads carried on the back in study 1. Allother physiological variables were consistent with changes in oxygen consumption. Conclusion:The data provides no support for the 'free ride' hypothesis for head-loading although there is some evidence of energy saving mechanisms for back-loading at low speed/load combinations. Investigating the large individual variation in response may help in identifying combinations of factors that contribute to improved economy.2