diff --git a/rate_limited/calls.py b/rate_limited/calls.py
index b626e36..d843a46 100644
--- a/rate_limited/calls.py
+++ b/rate_limited/calls.py
@@ -3,6 +3,8 @@
 from inspect import signature
 from typing import Any, Callable, List
 
+Result = Any
+
 
 @dataclass
 class Call:
@@ -10,7 +12,7 @@ class Call:
     args: tuple
     kwargs: dict
     num_retries: int = 0
-    result: Any = None
+    result: Result = None
     exceptions: List[Exception] = field(default_factory=list)
 
     @cached_property
diff --git a/rate_limited/resources.py b/rate_limited/resources.py
index b1c9c67..cd4d8c5 100644
--- a/rate_limited/resources.py
+++ b/rate_limited/resources.py
@@ -1,9 +1,9 @@
 from collections import deque
 from dataclasses import dataclass
 from datetime import datetime, timedelta
-from typing import Any, Callable, Optional
+from typing import Callable, Optional
 
-from rate_limited.calls import Call
+from rate_limited.calls import Call, Result
 
 Unit = float
 
@@ -21,7 +21,7 @@ def __init__(
         quota: Unit,
         time_window_seconds: float,
         arguments_usage_extractor: Optional[Callable[[Call], Unit]] = None,
-        results_usage_extractor: Optional[Callable[[Any], Unit]] = None,
+        results_usage_extractor: Optional[Callable[[Result], Unit]] = None,
         max_results_usage_estimator: Optional[Callable[[Call], Unit]] = None,
     ):
         """
diff --git a/rate_limited/runner.py b/rate_limited/runner.py
index f6d706e..ae119d4 100644
--- a/rate_limited/runner.py
+++ b/rate_limited/runner.py
@@ -5,9 +5,9 @@
 from concurrent.futures import ThreadPoolExecutor
 from inspect import signature
 from logging import getLogger
-from typing import Any, Callable, Collection, List, Optional, Tuple
+from typing import Callable, Collection, List, Optional, Tuple
 
-from rate_limited.calls import Call
+from rate_limited.calls import Call, Result
 from rate_limited.exceptions import ValidationError
 from rate_limited.progress_bar import ProgressBar
 from rate_limited.queue import CompletionTrackingQueue
@@ -23,7 +23,7 @@ def __init__(
         resources: Collection[Resource],
         max_concurrent: int,
         max_retries: int = 5,
-        validation_function: Optional[Callable[[Any], bool]] = None,
+        validation_function: Optional[Callable[[Result], bool]] = None,
         progress_interval: float = 1.0,
         long_wait_warning_seconds: Optional[float] = 2.0,
     ):