diff --git a/Quake/cl_main.c b/Quake/cl_main.c
index 78440e54..bb42cecc 100644
--- a/Quake/cl_main.c
+++ b/Quake/cl_main.c
@@ -600,7 +600,7 @@ CL_ResetTrail
 */
 static void CL_ResetTrail (entity_t *ent)
 {
-	ent->traildelay = 1.f / 72.f;
+	ent->traildelay = 1.f / MAX_PHYSICS_FREQ;
 	VectorCopy (ent->origin, ent->trailorg);
 }
 
@@ -618,7 +618,7 @@ static void CL_RocketTrail (entity_t *ent, int type)
 		return;
 	R_RocketTrail (ent->trailorg, ent->origin, type);
 
-	ent->traildelay = q_max (0.f, ent->traildelay + 1.f / 72.f);
+	ent->traildelay = q_max (0.f, ent->traildelay + 1.f / MAX_PHYSICS_FREQ);
 	VectorCopy (ent->origin, ent->trailorg);
 }
 
diff --git a/Quake/host.c b/Quake/host.c
index e3e04755..0a7b605e 100644
--- a/Quake/host.c
+++ b/Quake/host.c
@@ -59,7 +59,7 @@ jmp_buf host_abortserver;
 jmp_buf screen_error;
 
 byte  *host_colormap;
-float  host_netinterval = 1.0 / 72;
+float  host_netinterval = 1.0 / MAX_PHYSICS_FREQ;
 cvar_t host_framerate = {"host_framerate", "0", CVAR_NONE}; // set for slow motion
 cvar_t host_speeds = {"host_speeds", "0", CVAR_NONE};		// set for running times
 cvar_t host_maxfps = {"host_maxfps", "200", CVAR_ARCHIVE};	// johnfitz
@@ -117,11 +117,11 @@ Max_Fps_f -- ericw
 */
 static void Max_Fps_f (cvar_t *var)
 {
-	if (var->value > 72 || var->value <= 0)
+	if (var->value > MAX_PHYSICS_FREQ || var->value <= 0)
 	{
 		if (!host_netinterval)
 			Con_Printf ("Using renderer/network isolation.\n");
-		host_netinterval = 1.0 / 72;
+		host_netinterval = 1.0 / MAX_PHYSICS_FREQ;
 	}
 	else
 	{
@@ -129,7 +129,7 @@ static void Max_Fps_f (cvar_t *var)
 			Con_Printf ("Disabling renderer/network isolation.\n");
 		host_netinterval = 0;
 
-		if (var->value > 72)
+		if (var->value > MAX_PHYSICS_FREQ)
 			Con_Warning ("host_maxfps above 72 breaks physics.\n");
 	}
 }
diff --git a/Quake/quakedef.h b/Quake/quakedef.h
index c831f218..b675532f 100644
--- a/Quake/quakedef.h
+++ b/Quake/quakedef.h
@@ -65,6 +65,8 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #define DIST_EPSILON (0.03125) // 1/32 epsilon to keep floating point happy (moved from world.c)
 
+#define MAX_PHYSICS_FREQ (72.0) // Physics beyond 72Hz is broken
+
 #define MAX_MSGLEN	 64000 // max length of a reliable message //ericw -- was 32000
 #define MAX_DATAGRAM 64000 // max length of unreliable message //johnfitz -- was 1024