"Fast accelerating" and "Slowly accelerating"

In a question on the Physics SE site I wanted to formulate the following sentence (a sentence consisting of two cases):

1. The fast accelerating person is in front. 2. The slowly accelerating person is in front.

In more words I can clarify this:

1. The person who is accelerating with a larger acceleration is in front. 2. The person who is accelerating with a smaller acceleration is in front.

I feel that the first version which is written in fewer words is wrong. The words "fast" and "slowly" don't seem consistent and might not fit correctly in the sentence.

Can the first version above be fixed while keeping it short and concise?

• Idiomatically. the construction is far more likely to be: The person accelerating fast / slowly is in front. Apr 20, 2021 at 8:35
• I would use “higher acceleration” and “lower acceleration”. Acceleration is already a rate of increase, so a higher acceleration means something is increasing more quickly than a lower acceleration. The person with higher acceleration... Apr 20, 2021 at 10:57
• @RonaldSole - Assuming the fast/slow definition is a comparison between the two people (i.e. a rapidly accelerating person is defined in relation to the slowly accelerating person) would it be better to say The person accelerating faster/slower is in front. Apr 20, 2021 at 12:41
• Grammatically, that's fine - although I have no idea of the context. Apr 20, 2021 at 18:04

The adjectives higher and lower are more appropriate to use than faster and slower for describing acceleration, which is already a rate of increase.

Though all four adjectives are found on Ngram, lower beats slower in the last seven decades, and higher beats faster in the last six.