diff --git a/docs/theodolite-benchmarks/load-generator.md b/docs/theodolite-benchmarks/load-generator.md
index 8fefa19617263784cdf102d91e93ad492adbe63c..5ae10d16a50aaa16a76975d8127ef379508b1a37 100644
--- a/docs/theodolite-benchmarks/load-generator.md
+++ b/docs/theodolite-benchmarks/load-generator.md
@@ -55,6 +55,7 @@ The prebuilt container images can be configured with the following environment v
 | `KAFKA_LINGER_MS` | Value for the Kafka producer configuration: [`linger.ms`](https://kafka.apache.org/documentation/#producerconfigs_linger.ms). Only used if Kafka is set as `TARGET`. | see Kafka producer config: [`linger.ms`](https://kafka.apache.org/documentation/#producerconfigs_linger.ms) |
 | `KAFKA_BUFFER_MEMORY` | Value for the Kafka producer configuration: [`buffer.memory`](https://kafka.apache.org/documentation/#producerconfigs_buffer.memory) Only used if Kafka is set as `TARGET`. | see Kafka producer config: [`buffer.memory`](https://kafka.apache.org/documentation/#producerconfigs_buffer.memory) |
 | `HTTP_URL` | The URL the load generator should post messages to. Only used if HTTP is set as `TARGET`. | |
+| `HTTP_ASYNC` | Whether the load generator should send HTTP messages asynchronously. Only used if HTTP is set as `TARGET`. | `false` |
 | `PUBSUB_INPUT_TOPIC` | The Google Cloud Pub/Sub topic to write messages to. Only used if Pub/Sub is set as `TARGET`. | input |
 | `PUBSUB_PROJECT` | The Google Cloud this Pub/Sub topic is associated with. Only used if Pub/Sub is set as `TARGET`. | |
 | `PUBSUB_EMULATOR_HOST` | A Pub/Sub emulator host. Only used if Pub/Sub is set as `TARGET`. | |