diff --git a/db.py b/db.py
index 24b7e72..db953ad 100644
--- a/db.py
+++ b/db.py
@@ -1,5 +1,6 @@
 import os
 import psycopg2
+import numpy as np
 from psycopg2.extras import RealDictCursor
 from datetime import datetime
 from urllib.parse import urlparse
@@ -505,6 +506,17 @@ class DataBase():
         total_span = date_range.days or 1
         relative_positions = [(date - min_date).days / total_span for date in start_dates]
 
+        # Convert relative positions and scaled estimated 1RM values to numpy arrays
+        x = np.array(relative_positions)
+        y = np.array(estimated_1rm_scaled)
+
+        # Calculate the slope (m) and y-intercept (b) of the line of best fit
+        m, b = np.polyfit(x, y, 1)
+
+        # Generate points along the line of best fit
+        y_best_fit = [m * xi + b for xi in x]
+        best_fit_points = zip(y_best_fit, relative_positions)
+
         # Create messages and zip data for SVG plotting
         messages = [f'{t["repetitions"]} x {t["weight"]}kg ({t["estimated_1rm"]}kg E1RM) on {t["start_date"].strftime("%d %b %y")}' for t in topsets]
         data_points = zip(estimated_1rm_scaled, relative_positions, messages)
@@ -514,5 +526,6 @@ class DataBase():
             'exercise_name': topsets[0]['exercise_name'],
             'vb_width': vb_width,
             'vb_height': vb_height,
-            'data_points': list(data_points)
+            'data_points': list(data_points),
+            'best_fit_points': list(best_fit_points),
         }
\ No newline at end of file
diff --git a/requirements.txt b/requirements.txt
index afa1e0f..808f5ae 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -7,4 +7,5 @@ flask-htmx==0.2.0
 python-dateutil==2.8.2
 minify-html==0.10.3
 jinja2-fragments==0.3.0
-Werkzeug==2.2.2
\ No newline at end of file
+Werkzeug==2.2.2
+numpy==1.19.5
\ No newline at end of file
diff --git a/templates/partials/sparkline.html b/templates/partials/sparkline.html
index 43220c0..9265280 100644
--- a/templates/partials/sparkline.html
+++ b/templates/partials/sparkline.html
@@ -1,5 +1,5 @@
-{% set fill = "#dcfce7" %}
-{% set stroke = "#bbf7d0" %}
+{% set fill = "#2ca02c" %}
+{% set stroke = "#2ca02c" %}
 {% set stroke_width = 4 %}
 {% set margin = 2 %}
 
@@ -11,6 +11,14 @@
     {% endfor %}
 {% endmacro %}
 
+{% macro path_best_fit(best_fit_points, vb_height) %}
+    {% for value, position in best_fit_points %}
+        {% set x = (position * vb_width)+margin %}
+        {% set y = (vb_height - value)+margin %}
+        {% if loop.first %}M{{ x }} {{ y }}{% else %} L{{ x }} {{ y }}{% endif %}
+    {% endfor %}
+{% endmacro %}
+
 {% macro circles(data_points, vb_height) %}
     {% for value, position, message in data_points %}
         {% set x = (position * vb_width)+margin %}
@@ -22,7 +30,7 @@
                    on mouseout
                    add .hidden to #popover-{{ unique_id }}">
         </circle>
-        <circle cx="{{ x }}" cy="{{ y }}" r="1" stroke="blue" fill="blue"></circle>
+        <circle cx="{{ x }}" cy="{{ y }}" r="1" stroke="{{ stroke }}" fill="{{ fill }}"></circle>
     {% endfor %}
 {% endmacro %}
 
@@ -38,7 +46,8 @@
     <!-- Popover content will be dynamically inserted here -->
     </div>
     <svg viewBox="0 0 {{ vb_width + 4 }} {{ vb_height + 4 }}" preserveAspectRatio="none">
-        <path d="{{ path(data_points, vb_height) }}" stroke="blue" fill="none" />
+        <path d="{{ path_best_fit(best_fit_points, vb_height) }}" stroke="gray" stroke-dasharray="2,1" fill="none" stroke-opacity="40%"/>
+        <path d="{{ path(data_points, vb_height) }}" stroke="{{ stroke }}" fill="none" />
         {{ circles(data_points, vb_height) }}
     </svg>
 </div>