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Online Ph.D Defence by Kristoffer Larsen Norheim

Online Ph.D Defence by Kristoffer Larsen Norheim

Kristoffer Larsen Norheim will defend his PhD thesis: “Physical fitness among older manual workers"


12.06.2020 kl. 13.00 - 16.00



13.00             Opening by the Moderator
13.05             PhD lecture by Kristoffer Larsen Norheim
13.50             Break
14.00             Questions and comments from the Committee
                      Questions and comments from the audience at the Moderator’s discretion
16.00             Conclusion of the session by the Moderator

Due to the current circumstances the Ph.D defence will take place online via Skype for Business. If you wish to attend, please send an email to Kristine Uldal Knudsen before 10. june 2020 at 12:00.

Evaluation committee

The Faculty Council has appointed the following adjudication committee to evaluate the thesis and the associated lecture:      

Professor Karen Walker-Bone
University of Southampton
United Kingdom

Professor Clas-Håkan Nygård
Tampere University

Associate Professor Andrew J.T. Stevenson
Aalborg University

Professor Pascal Madeleine
Aalborg University


Life expectancy has increased over the last decades. To accommodate the growing population of older adults, retirement age is currently being raised in many countries. Because aging is associated with a decline in physical fitness, this may be problematic for workers in physically demanding occupations. Although regular physical activity is an important component in slowing the aging process, controversy exists regarding the influence of manual work on physical fitness. Especially for older adults, very little knowledge exists regarding the influence of age and manual work on physical fitness. Delineating age-related changes in physical fitness among older manual workers could point toward physical deficiencies that should be targeted for future interventions. This could provide a better work ability and secure a meaningful retirement for all workers.

The overall aim of this thesis was to investigate physical fitness among manual workers in their last two decades of working life. Further, it aimed to investigate the effects of musculoskeletal complaints on motor control tasks and fatigue development. To accomplish this, a series of five studies were conducted. Study I described the protocol for the experimental assessments that constituted the four latter cross-sectional studies. In Study II it was demonstrated that age and the stage of musculoskeletal pain (acute vs. chronic) differentially affects the structure of handgrip force variability in manual workers. Similarly, Study III showed an age-dependency on the effects of musculoskeletal pain on lower extremity function and dynamic balance. In Study IV, the response times during a hammering task were markedly slower for older manual workers compared with younger controls. Surprisingly, this was not accompanied by differences in hammering accuracy. Lastly, results from Study V indicated that all domains of physical fitness deteriorates with increasing age in manual workers. Greater strength and body size, but poorer cardiorespiratory fitness and pulmonary function was found compared with general populations.

In summary, the present thesis indicated that manual workers do not improve their fitness by being in jobs in which they are physically active every day. Especially cardiorespiratory fitness, pulmonary function, and motor control seemed to be negatively affected, whereas muscle strength may be maintained to some extent in these older workers. Of note, physical fitness was more strongly associated with physical work ability after age 60, suggesting physical fitness as a limiting factor only among the oldest workers.  Future studies are encouraged to investigate the effects of interventions aiming at increasing cardiorespiratory fitness and reducing fat mass among older manual workers.


HST - Department of Health Science and Technology


Skype for Business

Registration Deadline

10.06.2020 kl. 12.00

Register at


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