There is a common notion that native inhabitants of Africa are inherently lazy compare to native of temperate regions (Europe, North America, parts of Asia). For some, such attitude breeds low productivity and thus partly explains the snail-moving pace of economic development. Many have called for another kind of revolution in Africa, this time in work attitude. As a writer on this subject, I am not opposed entirely to the assertion as I am also irritated by some of our generally poor work attitude. But as a scientist, I have sought to look into Human and Work Physiology to see if there could be other reasons for the largely held opinion of the synonymy of the words lazy and Africa. What I found made me questioned whether it is that they are 'lazy' or rather have 'reduced work attitude'. Please note that though the focus is on Africa, the arguments extend to the tropics (Africa, South America, etc) because of shared climatic characteristics. Hence the term tropics will be used more often and impliedly in this article. The term tropical region refers to regions situated on either side of the equator, whereas temperate region refers to regions that lie between the tropics and the polar circles. As we often say the devil is in the details…. Temperature (Heat), Energy Levels and Work Capacity

Average temperature in the tropics is 25°C. Various scientific investigations in work physiology indicate that for a healthy, heat-trained worker, continuous work of 300 kcal/h (bush-clearing, hoeing, heavy weeding) is only permissible up to a temperature of 27°C. Exceeding this temperature leads to fast overheating of the body, rapid decline of physical performance, and lowering energy level. This shows that for tropical inhabitants working outdoors under temperature ranging between 28-36°C, they will experience significant lowering of energy levels resulting in reduced work capacity. To restore the thermal equilibrium of the body, several hours of rest are necessary by means of relaxation and siestas. Note that the engagement in these culturally accepted methods of energy conservation and replenishing of energy levels undoubtedly reduces the hourly productivity of heat exposed workers. Such losses in productivity leads many to the conclusion that the tropical man is not efficient, is not hardworking and in other words 'lazy'. Is this perception wholly right…

Reduced Work capacity: A normal Physiological Response

Generally when you are cold you perform activity to keep warm hence 'Cold Climate’ incites to labour and action. By extension, it can be said that ‘Hot Climate’ requires of individuals quiet and rest and slowing down. Well, according to climate change researchers, the slowing down of work as a defense mechanism during severe heat exposure is labeled ‘autonomous adaptation’. You see, so lazing about is scientific, in fact a normal physiological response. Well such mechanism is somewhat observed even among natives of temperate regions. For instance, we see active Europeans who work with all their strength during winter slowing down or even abandoning their labour during few days of summer, talking and gesticulating in the shade, besides a lunch-stand, sitting by watering places or strolling about. Therefore it comes as no surprise if native inhabitants of the tropics who have to endure high temperatures slow down a bit during work. Certainly this will reduce productivity yet it is a necessary evil.

Heat exposure index: Wet Bulb Globe Temperature (WBGT)

To protect workers from excessive heat, a number of indices such as WBGT have been developed. WBGT is used to assess the proportion of a working hour during which a worker can sustain work and the proportion of that same working hour that he or she needs to rest to cool the body and maintain core body temperature below 38°C. Using this index, Kjellstrom et al (2009)* estimated a ‘work capacity’ for selected heat exposure and work intensity levels. Their conclusion was that work capacity rapidly reduces as the WBGT exceeds 26–30°C. Thence in Africa (tropics) where temperature is mostly around 28-38°C, 'reduced work capacity' is the prime suspect and not inherent laziness…

Thus far, native tropical inhabitants (Africa) may not necessarily be inherently lazy but have reduced work capacity. Though, the bodies of the inhabitants of the two regions (tropic and temperate) tire out while working, the frequency and duration of rests is far higher for tropical inhabitants than those of the temperate. In temperate regions, heaters are provided at work places to keep temperature at levels conducive for ‘sustained work capacity’. Work capacity in Africa can be boosted through sufficient ventilation and where affordable air conditioners to avoid temperatures inimical to sustained work capacity. Such measures are important in the face of climate change effect (increasing temperature) in the tropics.

By: William K. Dumenu

kdumenu@gmail.com.

* Kjellstrom T., Holmer I., and Lemke B. 2009. Workplace heat stress, health and productivity – an increasing challenge for low and middle-income countries during climate change. Global Health Action, Vol 2 (2009).