Normalised Graded Pace (NGP)

Normalized graded pace (NGP) is a metric used in running to provide a more accurate representation of the pace achieved during a run, especially when running on uneven terrain or varying elevation. It takes into account the impact of changes in elevation on the overall pace.

On some platforms, for example Strava, NGP is called Grade Adjusted Pace (GAP).

When you run on hilly terrain, your pace can vary significantly depending on whether you’re running uphill or downhill. Uphill sections typically slow you down, while downhill sections often allow you to run faster. Normalized graded pace aims to give you a single pace value that reflects the effort you put in, considering both uphill and downhill portions of your run.

To calculate the normalized graded pace, the course of your run is divided into segments, which can vary in length. These segments are typically defined based on changes in elevation. For example, if you have a hilly course, each uphill and downhill section can be considered a segment.

The calculation of NGP involves adjusting the pace of each segment based on the grade (slope) of that segment. The pace is adjusted to a hypothetical pace that you would have maintained if you were running on a flat surface. This adjustment accounts for the additional effort required when running uphill and the potential advantage gained when running downhill.

By factoring in the adjustments for uphill and downhill sections, the normalized graded pace aims to provide a more accurate representation of the effort you put into the run, allowing for better comparisons of performance across different terrains and courses.

An important point to bear in mind is that the research to evidence such calculations are relatively sparse, and as one can imagine generic. This can often lead to questionable figures. Particularly at extremes of grades, or over very undulating terrain.

References & Further Reading

1. Staab JS, Agnew JW, Siconolfi SF. Metabolic and performance responses to uphill and downhill running in distance runners. Med Sci Sports Exerc. 1992 Jan;24(1):124-7. PMID: 1548986.
2. Minetti AE, Moia C, Roi GS, Susta D, Ferretti G. Energy cost of walking and running at extreme uphill and downhill slopes. J Appl Physiol (1985). 2002 Sep;93(3):1039-46. doi: 10.1152/japplphysiol.01177.2001. PMID: 12183501.
3. Vernillo G, Giandolini M, Edwards WB, Morin JB, Samozino P, Horvais N, Millet GY. Biomechanics and Physiology of Uphill and Downhill Running. Sports Med. 2017 Apr;47(4):615-629. doi: 10.1007/s40279-016-0605-y. PMID: 27501719.
4. Khassetarash A, Vernillo G, Martinez A, Baggaley M, Giandolini M, Horvais N, Millet GY, Edwards WB. Biomechanics of graded running: Part II-Joint kinematics and kinetics. Scand J Med Sci Sports. 2020 Sep;30(9):1642-1654. doi: 10.1111/sms.13735. Epub 2020 Jun 17. PMID: 32485036.