slow finishing kick

That tends to be how it goes. A kick really comes from still having energy to run fast at the end of a race. Did you see Cole Hocker dropping a 23.high second 200m in the Olympic final? No because it was a sub 3:30 race and not a 3:35-3:40 race.

Think about it like this though, speed endurance and aerobic strength are pretty key for a kick. The aerobic strength gets you there without dying, the speed endurance let’s you sprint fast and long at the end. Here’s some perspective.

2 4:30 milers. One has a 52 second 400m, while the other has a 57 second 400m. In a race where the pace is sitting at 4:40-4:45 until the last 300m who wins? My money is on the 52 guy.

1) Build speed-relevant leg strength & muscular endurance during base training. Not an expert; I don't mean to use those terms in a technical sense, just colloquial description.

Long-sprinter-style tempo sessions like 20-24 x 100m with 2-3 min recovery @ 75-80% 100m PR pace (think of it like a "stride workout"). So, if your best 100m is 12.0 sec, this session would be at 15-16 sec. Done once per week, after an easy run, not immediately before or after a workout day.

And/or 8-12 x 200m-ish hills, 3 min walkdown rec, at mile effort.

2) Work on top end speed. 5 x (30m accel, 30m max sprint, 30-40m stride out / cruise decel). Late Base Phase thru early-mid season.

3) 4 x 150m with 5 min rest. Smooth accel curve, hard full sprint effort down the straight. Done after light warmup with some drills and strides, do not run 2-3 miles like a distance guy before this. Feel free to lightly jog a few miles afterward, though. Mid-late season.

4) 200m repeats for 800m runners (this will benefit your kick in the mile / 2 mile, and it will help maintain/improve your 800m race pace). Start early season with 8 x 200m @ current 800m pace with 1' rec, progress to 3 x (4 x 200m) r1'/r5' midseason. For more advanced runners, decrease rec between reps down to 30", and/or add a 4th set.

5) Train to run fast, after running hard. Late season example sessions:

500m @ current 800m pace, 3 x (jog curve, sprint straight).

1000m @ current mile pace, 6 x (jog curve, sprint straight).

1200m @ 2-mi pace, 800m @ mile pace, 400m all out. Let your coach determine your recovery, based on your personal strengths/weaknesses and fitness.

BUT your best bet, right now, in April of your track season? Talk to your coach. He/she probably already has a plan in place to progress you thru the season. Maybe you're not supposed to have a strong kick right now and based on the plan, that will come later.