Loom & Effort Signature
Every ride has a shape. Not just a power curve, but a full distribution of effort across every duration and intensity. RaceProof captures this as an Effort Signature and renders your season through Loom, a visualization that makes development visible without reading a single number.
Effort Signature
An Effort Signature is a ride rendered as pure color against the Power Threshold Array. Where a power curve plots watts against time in a single line, an Effort Signature captures the full distribution of effort across all seven bioenergetic thresholds, the complete shape of what your body did during a ride.
The PTA identifies seven transition points on the power-duration curve, each corresponding to a shift in energy system dominance. From the neuromuscular ceiling of a sprint (PT-N) through the glycolytic burn of sustained anaerobic effort (PT-G, PT-X) to the oxidative demands of threshold riding (PT-O, PT-V, PT-T), each threshold marks where physiology actually shifts, not where a conventional fixed time window approximates a shift.
The Effort Signature maps this physiological profile to a color spectrum. Sprint power burns gold at the top. Threshold effort glows deep plum at the bottom. The color tells you what kind of work was done and where the body's energy systems were engaged.
A criterium produces a signature dominated by gold and amber at the top (repeated sprints, neuromuscular and glycolytic demands) with threshold barely present. A tempo ride shows deep plum filling the base with the upper register quiet. A road race that ends in a sprint shows the full spectrum. The geometric pattern of the seven thresholds IS the fingerprint of that ride.
Loom
Loom takes the Effort Signature of every ride and weaves them into a single image. Each vertical strip is one ride, arranged chronologically left to right. Within each strip, the vertical axis maps to the PTA spectrum, from neuromuscular power at the top to sustained threshold at the bottom. Your season becomes a textile of color and light.
The visualization borrows its structure from Ed Hawkins' warming stripes and applies it to individual athletic performance data. Where Hawkins used one stripe per year to show a planetary trend, Loom uses one strip per ride to show an athletic one. The design story behind this decision is told in The Shape of the Heat.
What the heat means
Each strip in a Loom rendering carries four visual channels. Together they encode the physiological state of the athlete at the time of each ride.
The veil manifests in three visible ways. Sharpness degrades as fatigue accumulates, blurring the crisp edges of a strip. Echoes let the residue of a hard session linger into subsequent strips, a long shadow cast by yesterday's effort. Bleed occurs when fatigue erodes the boundary between rides entirely, with color running across strips. Clean separation between strips means the body is absorbing the work.
Patterns, not numbers
A Loom rendering makes several things visible immediately without any numerical literacy.
Consistency. Dense, closely-spaced strips mean regular riding. Gaps appear as literal empty space. You can see a two-week break without counting days.
Fitness trajectory. A sequence that grows brighter over time is a rider building fitness. A sequence that dims is fitness eroding. The gradient tells the story.
Fatigue cycles. The veil accumulates over hard riding days, softening each strip. After rest, clarity returns. Overtraining appears as sustained veiling that never resolves.
Training residue. Echoes of yesterday's effort are visible in today's strip. A hard interval session casts a long shadow. Easy sessions fade quickly. The residue tells you how much the body is still processing.
Recovery quality. When color bleeds across strip boundaries, recovery isn't happening between sessions. Clean separation means the body is absorbing the work. Sustained bleed is a warning.
Energy system development. A rider focusing on sprint work shows gold-dominant strips. A rider building threshold shows deep plum developing at the base. Whole-curve development shows vivid color from top to bottom.
Peak form. The sharpest, most brilliant strips in the entire sequence are peak form: high fitness, low fatigue, full energy system engagement. You locate your best days by finding the brightest, crispest threads in the weave.
Where each threshold lives
Each threshold has a seat: its position in two-dimensional space defined by Threshold Power (watts) and Threshold Offset (the duration at which the transition occurs on the power-duration curve). Seven seats produce fourteen independent development signals, because each seat can move in either dimension independently.
Power can increase without the offset shifting. The sprint gets stronger but doesn't last longer. Offset can extend without the power changing. The sprint doesn't get stronger, but it endures further down the time axis. Both can move simultaneously. Each movement is a distinct signal about what the body is adapting to and how.
The four quadrants
When a seat is plotted relative to a baseline measurement, the axes define four quadrants of development:
Upper right is unambiguous development: more power, later offset. The system got stronger and more enduring. Lower left is regression in both dimensions. The other two quadrants tell a more nuanced story. Upper left means the system is more powerful but compressed in time: a stronger sprint that fades sooner. Lower right means endurance without power gains: the system doesn't produce more force, but it sustains output further down the time axis.
The Shape of the Heat tells the design story behind Loom, from textile climate art and warming stripes to Tufte's principles and the Banister/Coggan performance model.
The Racing Effect presents the population-level evidence that competitive racing produces measurable fitness development at every PTA threshold.
RaceProof Product describes the full platform including Effort Signature, Loom, Trust Score, Proof Network, and Cross-Source Intelligence.