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自動翻訳です。英語版が基準となり、表現は今後改善していきます。改善点があれば教えてください。

Beginner

投球速度

Definition

スローピッチソフトボールにおける投球速度とは、ボールが投手からプレートまで移動する速さのことで、通常は時速25~35マイルです。多くのリーグでは、レクリエーション性を保つために最高速度の制限を設けています。

スローピッチはレクリエーションでの参加を目的として設計されているため、最高速度の制限(プレート上、あるいは投手の手を離れる時点で時速35マイルとされることが多い)は、経験豊富な投手がカジュアルなリーグを圧倒してしまうのを防ぎます。合法な速度の範囲内でも、投手はタイミングを崩すためにペースを変えます。時速33マイルの投球の後に時速25マイルの投球を投げると、落下角度と到達時間が変わります。アークだけを意識して速度を意識していない打者は、遅い投球に対して遅れたり突っ込んだりしてしまいます。

Beginner tip

Throw your first few pitches at 60-70% effort to build arc consistency before experimenting with speed variation — consistency always beats velocity in slow pitch.

Advanced note

Develop two distinct release tempos. This means one at full speed and one 15-20% slower. This means that look identical until the ball leaves your hand. This keeps experienced hitters from reading speed tells early.

Example

投手が時速28マイルで投げた後、同じ腕の動きのまま時速22マイルまで落とすと、打者は前に突っ込んでポップフライを打ってしまう。

How it shows up on video

Compare the ball's travel distance in equal time intervals at the start and end of its flight. This means significant deceleration beyond 40% of initial speed suggests a very low-speed pitch. Watch how early the batter begins their stride trigger relative to release, as lunging forward indicates the hitter was fooled by a speed change. A radar gun reading at plate level is the most reliable confirmation of league compliance.

Common mistakes

  • Exceeding the league maximum speed limit with an aggressive delivery, risking ejection and illegal-pitch calls that hand the offense free bases
  • Using identical pitch speed on every batter, making timing trivially predictable after the first plate appearance of any given at-bat
  • Batters ignoring pitch speed variation and timing only to the arc peak, causing them to be reliably late or early on speed changes
  • Not checking league-specific speed rules before a tournament, since maximum speeds vary across associations and division levels

In SwingVantage Motion Lab

SwingVantage estimates pitch speed from frame rate and distance calibration in uploaded video, flagging speeds that approach or exceed the league maximum for pitcher review.

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Related guides & benchmarks

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