diff --git a/tokio/src/runtime/handle.rs b/tokio/src/runtime/handle.rs
index c5f2b6715..2024cffd3 100644
--- a/tokio/src/runtime/handle.rs
+++ b/tokio/src/runtime/handle.rs
@@ -70,7 +70,8 @@ impl Handle {
     #[cfg(feature = "rt-core")]
     pub fn spawn<F>(&self, future: F) -> JoinHandle<F::Output>
     where
-        F: Future<Output = ()> + Send + 'static,
+        F: Future + Send + 'static,
+        F::Output: Send + 'static,
     {
         match &self.kind {
             Kind::Shell => panic!("spawning not enabled for runtime"),
diff --git a/tokio/src/runtime/mod.rs b/tokio/src/runtime/mod.rs
index 686a5c262..2d5952420 100644
--- a/tokio/src/runtime/mod.rs
+++ b/tokio/src/runtime/mod.rs
@@ -299,7 +299,8 @@ impl Runtime {
     #[cfg(feature = "rt-core")]
     pub fn spawn<F>(&self, future: F) -> JoinHandle<F::Output>
     where
-        F: Future<Output = ()> + Send + 'static,
+        F: Future + Send + 'static,
+        F::Output: Send + 'static,
     {
         match &self.kind {
             Kind::Shell(_) => panic!("task execution disabled"),