**5. Conclusions**

The results of the present study enrich the existing literature regarding the physiological profile and the race pace characteristics of recreational marathon runners competing in a di fficult route, the Athens Marathon. Medium-level runners (finish time range: 194–225 min) have higher VO2 max, lactate threshold values, better running economy, greater oxygen fractional utilization at race pace and adopt a faster race pace in relation to their lactate threshold velocity than low-level runners (finish time range: 260–328 min). Furthermore, medium-level runners show no significant alterations in their pace due to terrain alterations in contrast to the low-level runners to whom the uphill part of the race leads to grea<sup>t</sup> reductions in race pace. Therefore, slower runners are more influenced by a hilly terrain and they decrease more their running velocity to complete this part of the race. Thus, careful planning of race pace should be considered so that pacing of the parts before the uphill would

be of such an intensity to avoid a large decrease in running velocity at uphill. Therefore, besides the focus on training for the improvement of important physiological parameters related to endurance performance, it is recommended that the selected race pace strategy be applied individually according to each athlete's level.

**Author Contributions:** Conceptualization, A.M. and I.S.; methodology, A.M., I.S., E.M.K., E.R. and H.D.; investigation, E.M.K. and E.R.; data analysis, A.M., I.S., E.M.K. and E.R.; writing—original draft preparation, A.M., I.S. and H.D.; writing—review and editing, A.M., I.S. and H.D.; supervision, I.S. and H.D. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** The authors wish to thank the recreational runners who participated in the study.

**Conflicts of Interest:** The authors declare no conflict of interest.
